It's also sometimes a necessary tactic to cover your team's ass. Very often, the people holding things up will blame another group on the project. Getting everyone on the same call so the bullshit can be called out in front of everyone can be necessary to protect your team's reputation.

Holdups: "Well, we can't start testing until Infrastructure builds our servers!"

Infrastructure: "You asked for a 3TB server. The largest in our environment is 1TB, and it handles [heavier thing than this]. Two weeks ago we suggested a smaller size to begin with and that we would increase it as need was demonstrated, asking for your confirmation before we continued. We also asked [group owning the vendor relationship] to see if we could schedule a chat with a technical resource at the vendor to help us better understand the need for something so far outside our standards.

We've not seen a response regarding our suggestion. Can you confirm that our suggested solution is acceptable during this meeting, or do you need to confer with other people in your department?"

Happens all the fucking time. Instead of admitting that the timeline isn't possible, or rightfully blaming the vendor for absurd requirements (no, we aren't giving you fucking domain admin), teams will just play pass the blame all the way to whatever department owns the deepest part of the tech stack or access management.

The easiest way to push back is to state how unambiguously bad their request was, and that they've not replied to you, in front of everyone. If you're lucky, all that takes is an email. If it's a project involving people who think they're too important to read email, then you need the call/meeting. Unfortunately those "too important" people are also the ones who have the biggest sway on the business.

It's stupid, but as long as people are involved in business, there will be people problems to solve. Those often don't work in the realm of "most efficient" or "most sensible".

Whatever your level of digust at it is, the soomer you learn to start looking at the "business politics" side of things the better you'll do.

This is also what good project managers are for. Unfortunately those are rare.