The ones that say we made that promise are basing it off something James Baker said, not any official agreement but here is what Gorby said about it. Yes I trust him more t5han Baker.
"In a 2014 interview, Gorbachev said as much: “The topic of ‘NATO expansion’ was never discussed. It was not raised in those years.”
A pretty good read on the subject.
https://www.cfr.org/backgrounder/why-nato-has-become-flash-point-russia-ukraine
Well, for the sake of argument, let's say Gorby's correct.
Adding 14 countries and expanding NATO nearly 1000 miles would still be cause for concern to Russia.
Adding Ukraine to that list would be pouring gas on a fire.