Classic trade protectionism by Indonesia. The country had also blocked Yahoo, Paypal, and Amazon before. But SCMP loves to present things from an anti-China perspective. Indonesia's e-commerce, supply chain, and retailers are not as developed as Thailand, Malaysia, or Singapore. So there is irrational fear of the more efficient competitors from China. Other than that, Indonesia has not done anything else that is outright provocative against China, unlike the Philippines.
Best case scenario, the products affected are made in China anyways - direct sales via Temu cuts out a whole industry of importers, distributors and local brick-mortar retail shops (as well as local eComm businesses)
Worst case scenario, the products from Temu compete directly with local made products which means manufacturing is lost, on top of the aforementioned distrubtion-retail/eComm businesses.
China too benefitted in protecting their domestic industries during the nascent growth years. Allowing immature domestic industries and processes to grow. As can be seen in a lot of "free trade" examples from the past few decades, developing nations with small/immature industries get absolutely dominated by western MNCs that come in with very slick marketing, polished products and the ability to tank losses in the expansion markets from the profits in their home markets. Local industries have absolutely no chance against that kind of global competition.
Now, with the efficiency of international logistics, the foreign competition doesn't even need to come in directly. By way of example. Amazon offers free shipping to SG from US. It started out with a min. of S$120, then $60 (when they opened a warehouse in SG), then $40 and now ... no minimum. Think about how much business they must be doing in SG to be able to commit to free delivery in SG due to having almost daily containers and flights coming into SG from their US logistics hubs. In that way, think about how much business is not going to local distribution/retail businesses if the product source is from the US and the money all flows to the US? On top of that, we also now have Taobao offering free shipping to SG on orders of ¥199 and above. This leads to a very prevalent consumer behaviour of online price checking while in retail shops. This creates a lot of undue pressure on domestic industries which struggle to replicate the process, volume and cost structure of these foreign mature markets. Yes, the consumer benefits. More choices, better service, cheaper prices, etc. But what's good for the people is not always good for the country.
Bottom line, it's not about what did China do to Indonesia or what is Indonesia trying to do to China. Indonesia is a very big market in itself - 4th most populous country in the world. Indonesia has the market size to support very robust domestic players which may then turn into global players. It should be correct that the Indonesian government should be looking out for Indonesia's best interest (assuming that's what they're doing).