I don't think it's a bad thing to have specialists that have intuition about what other specialists do; in fact, that's a core responsibility for being a senior

I don't think it's a bad thing to have specialists that have intuition about what other specialists do; in fact, that's a core responsibility for being a senior individual contributor. But, (and I covered this in my original comment), I think that this mediating labor is the role of product management, and there is a reason why product management is 100% a full-time job that cannot be skimped out on. I never understood why it needed to exist when I first started in my career, or I thought it was mostly a status-signaling BS role. However, the only way to mitigate that natural tendency of individuals to assume "it's 100% pure human nature to always assume that one's own piece is the most complicated or meaningful part of a project" is for a technical product manager to actually own the ramifications of all design and engineering decisions that are made and orienting the resultant product properly to the longterm strategic goals of the company. There is no substitute. Engineering and design direction are full-time roles in and of theirselves, and so too is product.