Because in a big company you’ll find some things are documented in a combination of jira and confluence while another are in big figma boards and nobody knows where to look (my gf’s company has exactly this problem).
Also in a big company you want to have two teams collaborate but one uses one tool set and the other a different stack and there aren’t enough licenses for both.
And so on. It’s like having each team use its own code formatting rules or coding standard.
(You probably wouldn't choose either for that from the beginning, but you start using Jira for issue tracking/feature planning, of Figma for feature design, and end up with them holding a lasting record of how the feature is intended to be.)
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For the second problem, I guess I don't have much to say because I haven't tried running a large company. I just have never heard any good reason to be stingy with licences. On the other hand, the time I have wasted and the extra work I have done to get around problems caused by upper managment being stingy with licences has cost a lot more than the licence would.
I guess this will immediately make people discard my opinion, but I don't actually feel very strongly about each team having its own formatting rules or coding standard. It's not hard to adapt to the local conventions and the consequences of formatting rules are incredibly local.
That is a position that has been lost ages ago; the desktop model has given way to the app model. Instead of having files and then programs that work with those, we these days have data enclosed inside apps.
Imagine adding a new app. Can you just delete the existing? Not necessarily, maybe some people need to use that so now you are supporting 2 apps. Maybe there is a lot of legal work to check the status of a new app. Maybe the new tool seems great but maybe once you have committed to it and taken a large amount of time and money migrating, maybe it doesn't scale well. Maybe a certain feature doesn't work like it needs to.
The problem with the idea of the collective is that not all people have skin in the game. It costs nothing for someone to say they prefer something to something else but how do you make sure that the people who use it the most have more say in the choice?
The truth is, the status quo is always easier than something new.
Either way, I don't see why the people doing the work should not be allowed to (collectively) choose their tools. That way you get both collaboration (because they picked one thing together) and the most appropriate tool for the work to be done.