Investing into increasing their fab capacity is the easiest business decision they'll ever make. And if they need finance they could get investors lining up around the block throwing money their way.
https://www.tomshardware.com/news/amd-chip-shortage-packagin...
Not in the enterprise market where AMD is almost completely absent so far.
A quick search showed that in 2017, AMD server market share was 1%, and in 2020 is expected to have reached nearly 10%[1] in 2019. This is still not the same as 15 years ago, but the market is also not the same, with cloud computing, and this increase is very expressive.
They are bringing IPC improvement with Epyc Milan and is pushing the same innovations towards the server market.
[1] https://www.hardwaretimes.com/amd-server-market-share-grows-...