That's a nice statistic, though I don't think the two are related. Given the definition of "mass shooting" I would guess that the majority of them were committed with a weapon that didn't fall under the ban. Most likely a pistol.
The real issues of gun violence has always been the ease of access to guns. If you look up the number of guns manufactured in the US it's been on an upward trend since 2008. Before that it was averaging 3 to 4 million per year. It's climb to 13 million per year last year and 11 million in 2021. I think that has had more impact than the lapse of the ban.
Having said that, I still think there is no reason someone should own an assault style weapon going forward. And just incase somebody wants to debate semantics my definition is a firearms with some combination of the following; a pistol grip, barrel inline with the stock or lack of a stock, collapsible or folding stock, rail system that allows for multiple attachments around the weapon, detachable magazine with more than 10 rounds, and a barrel length under a certain size.
I've also thought that maybe reticle sights with no magnification should be banned, but not sure how prevalent those are in mass shootings with AR type weapons.