As a counter-example, the Affinity family of Photo, Designer, and Publisher seem to be doing pretty well as a partial commercial replacement for Abobe CC. I don't know how many Serif employs, but I'd be surprised if it were thousands. It's true that Affinity does a lot less, especially preproduction stuff, but a lot of "light" Adobe users seem happy with it.

As for grep, there are plenty of newer attempts, like ripgrep, ack, and ag, too.