It's really not MS' fault. If some third-party add-in doesn't work with newest version.

While I think 2013 was a debacle... (taking away free add-in PQ & PP)

I've been using Office 365 for over 2 years now and love it (ProPlus for about a year).

Co-Authoring feature that replaced Shared Workbook, is working great so far.
And both PQ and PP are available without ProPlus now (albeit with fewer built in connectors).