5-6% are the composite nominal GDP growth rates of the Tigers after reaching 10K in GDPPC. 5-6% is not "easy"
For China it is achievable. It is still massively urbanising its rural population. Almost half of the population have an extremely low salary (Premier's claim) which also provided a very low economic base which can quickly start generating growth if appropriate policies ("common prosperity") and investments are made.
China is also still upgrading its entire industry value chain in order to start producing and exporting higher value goods which can start creating X times more wealth for the country than the old labour-intensive low-value industries and the low-jobs created by it.
China is also at the "gates" just before the start of the 4th Industrial Revolution. China is currently at the forefront for utilising this new paradigm shift which could act as another
forcewealth-multiplier for the country.
In addition a new regional trade agreement RCEP, will open up further opportunities for Chinese enterprises having a unified market of ASEAN countries and most importantly, for the first time having China-S.Korea-Japan in the same trade framework/deal. This is more of an increase of wealth than a simple 1 +1 + 1 =3.
Moreover, China has already started setting up clusters of cities with populations of dozens and hundreds of million of people. These initiatives have started recently and due to the huge undertaking we haven't seen any significant results from greater synergies. I estimate that by 2025, initial policies for each cluster will start showing
some results.
If this seems underwhelming to you, have no worries. With hundreds of millions of people in "cluster-economies" just having "some" results is equal to an economic earthuquake for supercharging growth in these areas/regions/clusters etc.
There are a lot more reasons why China can support such high growth in the future (e.g. Dual circulation strategy among others) but I would need another hour of typing which I am not willing to do.
The Chinese leadership, western media propaganda aside, is extremely competent and it is pursuing multiple vectors of growth so that if 1 strategy fails, China could still keep growing its gdp by a lot.
The only pitfall is the demographics, which is another matter altogether and is much more nuanced and complex than western propaganda would make you believe. I wouldnt term it as a crisis as of now but more of a "serious challenge+++", which could become a "crisis" if a serious turnaround on the TFR doesn't start happening in the following years