Maybe you could also try to get your head around my last employer who has over 400,000 internal devices (excluding BYOD), millions of external customers across every continent and has an IT department of just under 10,000. I suspect after that you may reflect on the true size of your university even if is considered an ONS large organisation.
You are engaging in a pi$$ing contest. My University has over 60.000 devices in the IPAM, and hundreds of IT support staff. That is not small by any stretch of the imagination. Just because your previous employer was larger does not make my current employer small. Once you are managing 50,000 devices you might as well be managing 100,000 or 400,000 it's meh.
The point I was trying to make was Openreach don't want to have multiple ways to power their ONT's nor do they want to supply them in blue, pink or black. Other than having serveral manufactures, one size fits all.
And the point I was making that it is fricking trivial to have an ONT that can be powered from an external PSU
OR or via PoE. Mikrotik can manage it in a sub £25 WiFi access point so it's perfectly possible to do, and the idea that it complicates things is laughable in the extreme.
Trying to bend every install so they have to have a power socket where the ONT is located is fine for a new build. It is not fine for retrofitting millions of houses where hundreds of thousands will not have a power socket in a suitable location. Frankly the fact the ONT does not fitn a 47mm deep double socket with fibre and ethernet connected from behind is a retrograde step IMHO.