Nothing has exactly the same experience as MS. I don't think there is a clone project for it.
The two you listed are your best options.
Does LibreOffice have any issues that prevent you using it? If not, it's probably that your expectations are set by your comfort and familiarity with Office and that is the problem you need to solve.
Probably an ad, but much more subtle if so. The old ones were so blatant. :)
What makes you do it with a smile? What does it give you that proton or tutanota doesn't?