Communicating "this is what I think of your work, some of it is negative but isn't intended as an attack against you" (without actually using any of those words, otherwise you run into the "my human trafficking shirt" problem) in a way that you're confident your criticisms won't be used against you, it's a skill you can and should train.
But it's work. Like, okay, social stuff is a part of the job, but when you're an engineer in a room with other engineers you'd like to be able to speak your mind without constantly simulating a PR team in your brain.
> speak your mind without constantly simulating a PR team in your brain.
Certainly not what I'm advocating. But I would say, that off-hand and unexamined opining in a collaborative setting can have a deleterious effect. Particularly if you're in a lead or senior position where your criticisms may often proceed unquestioned, even if they are based on faulty or misapplied intuitions.
In my time as a consultant, I've found I've communicated best and reached the best outcomes when I've refrained from speaking until I'm clear about what I'm saying, and why. The initial reticence allows time for less confident voices to speak their minds, and as a side benefit allow a new perspective to move the conversation.