As I recall the M$ came about around the time when Microsoft engaged in rather questionable business tactics. They were the largest IT company and still played super hard ball. They deliberately did "embrace, extend and extinguish" various software/protocols to create lock-in to their own proprietary technologies (IE55/HTML. Kerberos/LDAP, AOL/IM) to further their market dominance.

At the time, the M$ acronym was IMO well earned. These days it appears to be different. Microsoft still has a large dominance on the desktop, but appears to not be playing quite as hard ball anymore. Stuff like NodeJS on Azure and VSCode would simply not have happened in the early 2000. Whether they actually changed, time will tell.

As for other companies deserving a derogatory acronym, I think you can measure these companies with:

1) How much do they actually subvert/interfere with standards and other companies inventions to gain/maintain their market dominance?

2) Do they at all innovate to deserve their market position and/or give back?

Without much analysis, I think Adobe may actually deserve an Adob$. Here you have a company that still almost every year change their proprietary binary formats (.PSD, .AI, etc) forcing an entire creative industry to spend a lot on software that have largely not had any significant innovation for the last 10-15 years (the functions in Photoshop/Illustrator have more or less remained the same).

And it is the same lock-in as Microsoft Office has/had, because even if you decide to operate your creative business using only alternative software, your clients and suppliers won't.