That would be perfectly valid criticism. If they'd said "there's x and y competitors and they do [...] really well - might be something you'd want to look at be

That would be perfectly valid criticism. If they'd said "there's x and y competitors and they do [...] really well - might be something you'd want to look at because these are very heavily used features", that'd be really constructive feedback. But all noodly said was "theres already one" and solicited contributors.