I have an office now and it helps a bit, but normally I hide at home and turn off email and put Teams into dnd for these tasks
If you were agreeing with him and just adding to the argument, then my apologies.
Bookkeeping and management accountancy are not really similar professions. A bookkeeper is focused on data entry, and tends to be a small company generalist, adding up invoices, receipts and sales tax etc. I have been a purchaser ledger clerk (processing supplier invoices en masse) and it requires a different kind of concentration entirely. I am rubbish at that kind of work now, I think your mind changes as you progress to the more supervisory work. A management accountant is trying to turn the outputs of this work (amongst other things) into coherent management information, filling in the gaps and making judgements and estimates.
PMs, scrum masters and sales or business development types don't usually have the same kind of focus requirements during day to day. Sure, they also need deep focus when drawing up a detailed budget or doing roadmap planning or whatnot, but usually their day requires less focus and a broader contextual awareness instead.
So, obviously physicists, plumbers, bookkeepers, surgeons, mathematicians, all manner of creatives, designers, engineers, chemists and evolutionary biologists also need not to be disturbed while working. But their workplace is often cognisant of the fact.
Programmers often complain because the default setup in which they work (some kind of open plan office) and the roles they often interact with don't get the basics of what's needed.
If I needed to work on site, I'd regard an seperate office as a significant perk.