Not to mention the mass reports of crashing and calibration issues where sometimes you would have restart the song 4 or 5 times to get it back in sync, which to this day both still plagues the game even when played on Series X|S and PS5 consoles on the latest released Rivals update.

Going from what was considered the absolute high of the series that was Rock Band 3, launch RB4 had numerous issues with it, lack of online that would be sold later as pass akin to the PS3/360 era of doing things except it costed more than those passes on average.

You lost me at "Rock Band 4" and "thriving community" Rock Band 4 is the worst received Rock Band game in the series (And before you mention it, check reviews BEFORE Rivals was a thing.)