To be more specific, only microelectronics, the cutting edge, is where China is behind others about 2 to 5 years depending on who you ask. Ask some person in Washington DC, and they will say 10 to 20 years.
As for the mature nodes in semiconductors, China not only has sufficient production to satisfy its own domestic needs, it is also a top producer of such chips in the world.
To be behind 2 to 3 years from the leading edge in semiconductor manufacturing, is not really what we can considered to be that far behind or backwards. They are right there in the race.
How manufacturing works, is the product, whatever product, will not immediately latch onto the newest chip. The better chip and newest chip, will cost more. If product does not really need because that better chip does not make the product better, then they do not need it.
Huawei built the 5G network nation with a stockpile of 7nm chips from what I can gather. Their basestation needed that 7nm chip.
That is it.
The cutting edge of the semiconductor industry is the last battleground of this current tech war, at least this phase of it.
The Americans are quite ahead from what I understand in the life-science industries, in other words, big pharma making expensive drugs. In this area, I doubt the PRC will ever catch up, because Chinese society have different priorities.
So we see how Huawei and SMIC and all their partners do with the EUV, then after that, I really not expect much further fireworks like we saw before, like in the Huawei 5G versus the US government tech war, or this semiconductor tech war.