If your build fails because you can’t track down the literal ≠ in the code I would recommend just looking at the compiler error. I understand the concerns about == vs = more but the vast majority of LSPs (and some compilers) will catch that too.
I have also yet to see any IDE enable ligatures by default, at least VS Code and the JetBrains suite both require opting into them even though their default fonts support them.
I agree.