You can, because your feedback is constructive and specific.

If you said "idk, this phone just sucks, because i feel like it does and idk how it could be made better", that would fall under "useless complaints". But saying "my phone drops calls often" is a specific complaint with a very specific (implied) improvement suggestion ("make phone not drop calls").

So the cooking thing would be totally valid if the person just said "It was too salty?", allowing the relatively uneducated/unskilled to make claims about quality even though they could never reproduce it? That's not how the original claim was framed.

I agree thay even with "it was too salty", it could be entirely baseless. However, "it was too salty" is still infinitely better than "idk it isnt good". Even if "it was too salty" was incorrect. But that is purely a personal opinion, and imo there is nothing that can substantiate it much.