But this is not the super tic tac toe I know (and also implemented 10 years ago in college).
Here you play until all ttts are solved. The version I know, has a winner only if in the bigger grid there are three wins in a tic tac toe fashion.
Blazor is a big framework. It gives you a lot, but as a framework, also introduces stack complexity.
Being able to code on one C# codebase for a web application client and server is great. It's very fast. You can use modern C# syntax. You have component (CSS) isolation. You can switch and mix between runtime targets (server dom rendering and sending diff-updates or client-side app execution).
At work, we're using it for a webportal/webapp and I have not fundamentally regretted us using it. It's definitely not worse than anything else. For a productive development and product there's a little bit of framework knowledge you have to learn, but that's not different than any other framework. And docs are very good.
I love how fast it feels to use the end product too.