PHP debugging is fine. Conditional breakpoints, walking up the stack trace, interactive and in-place code execution at run-time meaning I can run code or change variables and it applies to the current execution. It's great.

Javascript is a nightmare to debug, but it's probably just as much to do with architecture than debugging tools. Of course it's hard to debug a dozen tiny libraries written in ES6, transpiled down to ES5, packed into a module loader and flung around asyncronously.

JS debugging is fine in native, dependency free code I write. My sense is that debugging was something a lot of newer developers found out about later in their education and as such they never noticed debuggability and tooling wasn't up to par with older tooling.