You make some good points, but in today's world in order to develop its military power and develop its economy and become inseparable from the world in supply and demand, which you define as hard power... China needs soft power to do it.
If other countries hate China, then other countries will sanction China and refuse to trade with it and surround it with military containment strategies. Then China's economic success and military power will suffer over time, as well.
The intangible actually precedes and causes the tangible. For example, a company's assets are tangible, but before it acquires those assets it needs a business plan.. the intangible. The same is true for countries. They need a favorable environment to grow and develop their hard power. In 1978 China's economy was weak and its military was weak. So how did it grow? Because it increased its soft power by opening and reform, and by seeking good relations with other countries. The world's favorable perception of China in 1978 was the intangible which made possible the future tangibles. It was the soft power that made possible increasing hard power. If it had continued down the closed path of Mao and acted belligerently towards the West, it could not have succeeded as well as it did.
The reality is that China needs as many friends as it can get. Key decisions are being made in other countries, like whether to supply China with technology or allow China into their markets, or sign deals with China. Besides using its existing hard power to convince these countries, China also needs to increase person-to-person ties, improve its image, and overall improve its soft power. Otherwise all the money in the world is not going to help it, as we see countries that really hate China are willing to suffer major economic penalties and take irrational decisions just to hurt China, if China is too hated.
So other members have already expressed their views so I will try to give my 2 cents without too much reiteration of their points.
Let’s examine one point at a time... first, the company asset and business plan example... a business plan isn’t soft power/intangible thing... in fact the business plan example further reinforces my ‘intangible things without a tangible base will in the end become irrelevant’ argument... a business plan merely describes the tangible plan by which the company or entrepreneur intends to take in order to gain profits... in order words the business plan (intangible thing) requires the reality of the situation (tangible base) in order to have any real effect... for your example the idea of the business itself would be the intangible (soft power) absent the tangible base (hard power)... let’s take the social media as an example to explain my point... Facebook was not the first social media site in the world but it became the most powerful and most successful, while it predecessors failed why? Because Zack Zuckerberg understood how to use the idea of social media (intangible) in the world at the time (tangible base).
Next let’s examine the China opening up example... there is in fact a real life example in history already... if you remember the ROC... when it first came into existence it was weak... very weak... so it had no hard power but courted the western countries and had a fairly good relationship... it was willing to work with the foreign power and yield at certain things and was moving towards democracy and multi party system, so it had or was gaining some soft power... so by your logic the ROC at the time would have been in a prefect situation to leverage its soft power, it’s relationship with the western power to improve its hard power, right? But that didn’t happen it was seen as weak, which it was, and no amount of soft power did anything, to the point that it was later invaded by the Japanese, which at the time had enormous hard power, why? Because it had no hard power/tangible base to protect itself and the reality of the world at the time simply didn’t allow for its development, everyone else was concerned about their own lands and people, the situation or tangible state of affairs wasn’t in the ROC’s favour and no amount of soft power changed that... fast forward to 1978 the beginning of the ‘opening up’... it was a multitude of factors that made China what it is today... namely real changes in the economy, or in other words changes in the tangible, if you remember, back in those times China was still viewed as a backward country and to be frank rightfully so, as that was a fact... so in terms of soft power it wasn’t exactly doing very well... but what was pushing all the companies to China was the cheap labour, tangible/hard power, if you will, it was a change in the dynamics of hard power or it can be viewed as China using what hard power it possessed... having hard power doesn’t have to mean that China was already extremely powerful that other countries have to listen to them... hard power/tangible power can be economics or population or recourses or a better term benefits... foreign companies and countries working with China at the time gain real term benefits (a shift of hard power, for both China and the foreign companies or countries) by using cheap Chinese labour (hard/tangible power) so they can manufacture at a cheap cost whilst selling at the same price or in simpler terms gain more profits/cold hard cash! If your example of soft power being a powerful force of change was actually true... then China would have begun developing in the late 50s and early 60s after simp-soviet split, when the western power did everything to try to gain China as an ally against the Soviets... in some way that was a gain of huge soft power for China... but nothing really came out of it... not until the Chinese applied its limited hard power by using and leveraging it population.
I think there is a misunderstanding that having hard power must mean the one possessing hard power is the king of the world... no, using carrots is also a means of applying hard power... China merely leveraged what hard power it had (the economic power of cheap labour, which in fact was enormous, at least when population of concern China had real hard power and was very powerful at that) to incentivise (give the carrot) foreign companies to work with them... while the stick was the economic forces for the companies that wasn’t working with China, which China didn’t have to apply to the companies themselves... the only difference is the point of view...