I think I've found between 10 and 15 legendaries since the update.
2 I use, 1 would be good if I was a different mech type and the rest are junk.
I've been really active on this game too. I'd hate to think the amount of time/money that would need to go into those mechs that have 5+ important legendary-only items. It seems like it would take a ridiculous amount of money and grinding to get, say, 2 plates, a mythical resistance module and 2-5 legendary-only weapons. Crazy.