Whoa, somehow I thought 67g zealios would be super heavy, so they are on par with Cherry MX Clear/Ergo Clear then? Good to know
"Ergo clears" are a custom mod with Cherry MX Clear stems and 62g Korean springs. Cherry Clears have their own unique spring that (to my knowledge) isn't used in any other MX switch, and is heavier than MX Blacks by a good bit (I think up to ~90-100g bottom out force? can't remember).
Stock MX light springs (blues, reds, browns) bottom out at roughly 55-60g. MX Blacks are closer to 80g bottom out weight, 60g actuation.
Zealios have smoother stems than Cherry MX Clears, so compared to a 62g Ergo Clear, a 65g Zealios would be very similar (less friction -> more force required to match a Cherry switch).
I trust Zeal when he says that Massdrop springs are stock Gateron springs, but I couldn't find any info on bottom out weights compared to Cherry springs. If someone could post that info that would be great, I'm interested in grabbing some Gateron Black springs but it's hard to find the info.