I am honestly not sure how blindsided blocks can help IOL?
If you blindside block someone, that's a clear Indicator that your pass set levels are off. Helping/double teaming isn't about blindside blocking.
I just think the development of IDL has been skyrocketing. 3-Techs and 1-Techs are getting way more athletic and technically sound. And the IOL cant close this development gap. I mean there is a reason elite inside DL get paid significantly more nowadays.
Probably schemes, blitz packages combined with elite pass rush moves can be a reason too.
Edit: Also who tf knows the metrics and grading process of PFF lol
I didn't know this is considered a blind side block now lol