Win 10 enterprise edition is not win 10 pro. Enterprise edition keys are used by people who need their software to have actual guarantees, like defense and aerospace.
Also people who want as much of the bloat and cruft cut out as humanly possible. I've been using W10 LTSC for years now as a daily driver, runs all of my games and apps no problem.
You're limited to 300 users on Microsoft 365 Business Premium, anyone over this limit will be on Microsoft 365 Enterprise, which includes an Windows Enterprise license.