A big part of that is that Blitz is a 2-node skill whereas Shadow Strike/Vire’s Might are 3-node skills, with one of them being dedicated to giving the skill baked-in CDR. There’s very little reason to seek out Blindside bonuses in gear to hardcap it either compared to Nidalla’s Justifiable Ends/Volcanic Stride so for all-intents and purposes, Blitz’s main damage just comes from 1-node meaning it uses substantially less skill points than it’s brothers.
It’s something I discussed before some of the minor Blitz buffs (like reducing the cooldown from 3.8s to 3.5s) but it seems like they don’t want to make Blitz into another encompassing movement spammable like Vire’s Might/Shadow Strike: