I've been using Chrome with uBlock Origin Lite and not even once I found a case when this version of uBlock was behaving differently (as less efficient) than the "full" uBlock Origin
Maybe I'm just lucky, but even this argument is quite ... meh
I've found it a bit like "what car did you drive in to work with today" in that any typical current and working car is not going to be a stark difference to a high end car in terms of how fast you get there... but you'd definitely notice a piece of crap with a donut, broken heating, and screeching brakes causing you problems if that's what you were comparing instead.
I.e. I can count the number of times I said "wow, uBO Lite didn't make this site usable but loading up Firefox with uBO and it worked fine" on one hand. At the same time, if I ever look and compare how much is actually getting blocked, uBO is definitely blocking way more. Doing a side by side compare of dozens of sites it becomes easier to see minor differences I wouldn't otherwise have noted, but may not have mattered as much.
I commented about this a few weeks ago here about this, but essentially: v2 allows you to block things you can't see, but you still probably don't want, like folks hiding cloud analytics behind CNAME cloaking to allow it to appear as a first-party site rather than Google Analytics, for example.
You won't "feel" this in your day-to-day browsing, but if you're concerned about your data being collected, v2 matters.
That's not sucking at blocking thats YouTube intentionally adding a delay to make it seem like their experience is degraded when it isn't. If you turn the slider up to full it only happens very rarely.
I'm sure this will all change eventually though and YouTube has a loophole planned so ad blocking on manifest 2.0 is impossible.
I'm not really sure of the actual mechanism, but on Firefox with a fully updated block list the delay doesn't seem to happen for me. Whereas I could never quite get rid of it on Chrome. This was a while ago, though, when they first introduced it.
I use uBlock Origin with Firefox on Linux, and it seems like that delay happens maybe on 30% of the YouTube videos for me, with no rhyme or reason to which ones. And reloading the same video multiple times show consistent behavior if it loads fast/slow, not sure what's going on.
Maybe I'm just lucky, but even this argument is quite ... meh