Not at all. To clarify, saying something is "over", without really saying what your plan is, is low effort.
"This is a problem, and here is what I/we should do", takes a bit more effort.
Firefox is still open source last I checked. You can still contribute, write bugs, write letters to the CEO, etc...
I'm only taking issue with tendency people have to throw shade without offering a solution.
"low effort" is a completely different statement from supporting monopolies. If that's what you actually meant, sure I guess.
But it's really hard for a normal person to do much about steering firefox other than helping raise a fuss.
Sometimes there isn't "a solution".