The point is evaluating your stack once in a while. Eventually, you may need to switch or it may be worthwhile, even if you can stick with your current stack at a disadvantage.

For an extreme example, WordPress with crap page builders. It may not have been "that bad" when you started with it. But by now its very much worthwhile to switch. You don't "need to", but you should.

Back to this post, maybe they really are at that point that slowly switching is worthwhile. At least partially, where it makes the most sense (they mention using some microservices written in Go).

Because writing web apps is boring as fuck, and evaluating switching provides a reason to stop coding in PHP, and write an article about how they still need to write PHP.

Go is really nice! Though I prefer using both instead of a single one. Still hoping to come across a problem which could be solved by running a Go library using FFI in PHP.