Almost anything you can do on Tiny Tapeout your can do on an FPGA and test it today (not wait 6-9 months to get silicon back) - if you are laying polygons yourself because you want to test out some novel circuit that TT is potentially a great idea.
On the other hand if you've learned logic design and want to spread your wings and make some real chips then TT is an educational experience - not only is the tooling different but often you need to understand stuff in depth that FPGA tooling kind of hides (because essentially FPGAs come pre routed) so it's a great way to take a small step into silicon design.
There's probably a large bunch of people who will make just one design because they can, just to say they did it.
I've taped out 4 CPUs on TT, I'm retired, I used to do chip design, TT has the same sort of scope as the logic blocks I was making 20 years ago - no one is going to be using it for manufacturing (you get just 1 die back)
Xilinx, Altera - there's also some really cheap stuff coming out of China (Tang Nano). Because they all have their own dev system you tend to choose the one you know
There's a standard for external add-ons called PMODs (small boards with external connectors or parts) tiny tapeout uses it too, picking a dev board with PMOD connectors is probably a good idea.
On the other hand if you've learned logic design and want to spread your wings and make some real chips then TT is an educational experience - not only is the tooling different but often you need to understand stuff in depth that FPGA tooling kind of hides (because essentially FPGAs come pre routed) so it's a great way to take a small step into silicon design.
There's probably a large bunch of people who will make just one design because they can, just to say they did it.
I've taped out 4 CPUs on TT, I'm retired, I used to do chip design, TT has the same sort of scope as the logic blocks I was making 20 years ago - no one is going to be using it for manufacturing (you get just 1 die back)