There's quite a range between "looking at compiler output is sometimes useful" and "optimizing assembly is one's day job".
We use it all the time, it's certainly not just a toy.
I have the luxury of having a build farm with a large range of compilers and platforms available, so I could use that to rig something like godbolt. But that'd be spending probably days on setting something up, + ongoing maintenance, instead of just using an existing thing that does the job? If I really were only doing this kind of thing, that'd probably be worth it to be able to customize etc. But I'm not. It being a service (and thus basically automatically a web tool) is a a valuable feature.
It's also a great tool to share and communicate results of such investigations. Again, easy for a web tool.
We use it all the time, it's certainly not just a toy.
I have the luxury of having a build farm with a large range of compilers and platforms available, so I could use that to rig something like godbolt. But that'd be spending probably days on setting something up, + ongoing maintenance, instead of just using an existing thing that does the job? If I really were only doing this kind of thing, that'd probably be worth it to be able to customize etc. But I'm not. It being a service (and thus basically automatically a web tool) is a a valuable feature.
It's also a great tool to share and communicate results of such investigations. Again, easy for a web tool.