HL2 definitely shows its age nowadays but I am always compelled to return every year or two.

It actually doesn't even matter what HL2 is like anymore, its impact on the industry is probably one of the most significant of all major releases, so much so that the engine built for it over 20 years ago still continues to be used to this day.

I have probably spent more time consuming content about Half Life than I ever did playing it.
There isn't much to say here other than if you never played it you really should.