Remind me again, which part of the world are most semiconductor devices made?

Seeing as your're going by your gut feeling as opposed to doing a quick 1 min google search:

1. Taiwan
2. South Korea
3. Japan/China
4. USA (Overtaken in 2019/20)

for as long as I’ve been alive China has been the international manufacturing hub for that stuff

The trend is that China will get around 25-30% of the market share in a decade. In that trend, with no changes permitted, China might need a few more decades before they produce more than 50% of the market share, so unless you have yet to be born and you're about to come clean about us inventing time travel in the future; you're mistaken.

Solar cells were developed in the US, but China is where they were mass produced.

You're using to "were", trying to make it sound like these periods overlapped. Americans started producing and selling the first practical solar cells more than half a century (1950s) before China even made a single one (2000s). Heck, and the first patents were half a century before that.

If China was already dominant in the field, then what is the whole commotion about China retaking Taiwan and them ordering chip fabs from the Netherlands? Stop reading headlines.