I don't think the issue today is that companies are afraid of investing the money. if there is a return to be had, the money will get invested.
I think there are four big issues that are preventing more investment in fabs
The first is that it's hard to get started. You need a lot of experienced engineers, and you need access to IP, or a really patient and long-term thinking set of investors that are willing to R&D for no return for a long long time. Those two factors are going to keep new players out of the Fab business - you can't just form a startup and jump right in and be competitive, unless you have some groundbreaking new tech under your belt (which, I won't discount could happen, but it's a lightning strike and extraordinarily rare)
The second is that it's risky, so investors don't like to put money into it. You see big, established players that had been world leaders get humbled in just a matter of a few years (Intel) when they hit engineering challenges. That can set them back for years/decades, assuming they get over the challenges and get back to parity. You see some companies just throw in the towel and not even attempt to compete at the cutting edge (GloFo, TI), and a lot of companies just get out of it entirely because the returns are really hard to justify for the risk (IBM, AMD, etc)
The third is that it takes a long time to get a fab up and running. This is why current players aren't out there racing to build new ones: by the time they get online, the demand for the products they would serve will be mostly gone, and it will be all shifted to next generation. Those next generation facilities are already in progress. No one wants to chase a short term bubble and get stuck with a lot of very expensive manufacturing capacity that they can't fully utilize. The manufacturers would ~much~ rather underserve, and have the price drift up to meet demand, than oversaturate, and watch the prices tank and destroy their ROI.
A fourth would be geopolitical - you won't see much investment in the US without some incentives. You won't see much investment in China without political involvement. You won't see investment in typical low-labor areas because of lack of skilled work force. There are few geographical areas that have the right mix of political climate, geographical requirements, economic conditions, and workforce