I think the real problem here is "decision making" as opposed to "collaboration"
I can't think of a single time where having someone else review my work or give me feedback is a meaningfully bad thing. It's an opportunity to learn. But getting feedback is different to making the final decision.
Instead, the real problem is the either 1) lack of knowing who makes the final decision or 2) requiring everyone must agree to a final decision. You will move a lot faster if you know who the final decision maker is, ideally have fewer (or only one person) making that final decision, and encourage people to make decisions quickly (most decisions are reversible anyway)