I think China has done immensely well in semiconductors since 2000. So well and so quickly (trailing second if not shoulder to shoulder with niche players who specialise in fab domain!) in fact that I suspect the field of semiconductors was certainly a priority to get proficient and competitive at as ordered by CCP plans. There are niche manufacturers of this tool and that machine in Germany, Netherlands, and Japan. TSMC manufactures better than anyone else on the planet. Netherlands has no 5nm tech... nothing. They have great lithography technology but that's like being able to build a wheel on a car so good, all the car makers come to them for the wheels. Now that wheels are banned for China, it's own wheels are good enough but not 1st place in the race good. That's now. China isn't behind these player individually because they hold fractions of the supply chain. China is involved in every domain of it and have only a few things left to become the same level as the leader in their respective field. The US is so threatened now by China's position in semiconductors that it's willing to disrupt the entire supply chain to hurt China, even if it hurts allies and itself - lost income, lower supply of chips, breakdown of trust between EU and US etc.
TSMC can transfer all the tech they want to the Americans. The Americans own Taiwan's ass so long as Taiwan needs to carry on this civil war with the ruling elites preferring to live as secondary vassal on the frontline even if it means handing everything they own to the Americans. This is the price of the tributory status of Taiwan under this dynamic. The Americans obviously want to disrupt China as much as they can but be VERY thankful to them that they waited this long to stop China from accessing the worlds best fabs and equipment. Prior to that, it would actually have forced China to more drastic measures because back twenty or so years ago, China was at 0 in IC fab.
0 to 1 is where China sucks. 1 to infinity is where it excels. Even back in 2015, China would have been considered a 0.5 in fab and pretty damn good at research and design. Right now, China's chip research, development, and design is shoulder to shoulder with the absolute best in the world - Japan, Taiwan, US, Korea. Literally second to none and LEADING many fields e.g. 5G chips. China's fab sucks compared only to the absolute best - Taiwan. It's only half a step to one full step behind the best. 7nm fab is PUBLICLY revealed as ready soon. China reveals little in fear of repercussion and drastic action from its enemy. If they're comfortable revealing they've got 7nm down pretty much, they may even be setting production up as we speak. 14/12nm is supposed to be already in production now. Various fab techs for 7nm are being funded with more attention than ever before. Probably even further - 5nm and 2nm R&D etc.
Even Taiwan buys lens from Japan/Germany and EUV machines from Netherlands. No one owns and controls the entire supply chain (well except US since it de facto controls all but China... Russia etc). Since China's only missing EUV (one solution to 7nm and beyond) and EPA tools, that's really much less a gap than it's being played out as here on this forum.
Sure the situation from the US is aggressive and this certainly disrupts China a lot. It's simply still so far from catastrophic some members here need to chill with the we need to attack Taiwan rhetoric and the CCP members and corporate leaders are traitors statements.
Without those corporate leaders and CCP members who insisted and allowed on buying foreign while building domestic abilities, China would not have made as much money from products and its products would not be as competitive. They also clearly HAVE BEEN working on domestic SC technologies otherwise China wouldn't be so capable and comprehensively capable at almost every single SC domain from design to manufacturing and all the small parts that allow this down to specific lens engineering and the bolts of the Chinese machinery used for DUV etc.