LEGO did 470m with rave reviews and was enough to make WB go full steam ahead with three (three!) more movies.
Animation houses are specialized and generally draw different demos with different experiences, so you're not just going to be better off doing a live action with those resources. It's still a different stream that can avoid the pitfalls of fully saturating your liveaction slate.
Spider-verse is getting even better reviews and could do close to LEGO. People just have no frame of reference for these types of films beyond the same logic that had LEGO Batman's performance making people shocked. 'It's LEGO and Batman! 1B WW!' Or thinking that CG animated features should all be Disney level takes to be a success (because it's Soider-Man?). That's just not the case.
Not to mention that Disney CG films have like twice the budget and marketing costs of Spider-verse for those takes and ancillary.
Emphasis is being put on LEGO Batman here because, before people started getting crazy with predictions, it was generally thought that Spider-verse doing 400m was likely and good; Sony would be thrilled with 500m. It has also been (wrongly) a reference point to the numbers for Spider-verse that we've seen so far when that just doesn't track.
LEGO Batman didn't do that terribly overseas, 136m versus the franchise peak of 211m. Spider-verse starting in a similar place to the LEGO Franchise doesn't mean that they will necessarily recreate the same mistakes, like having LEGO Batman and Ninja in the same year.
Animation in general gets a different audience, but Spider-verse is not getting the animation audience. Its audience breakdown is not much different than a regular superhero film. Which makes sense, given that it wasn't a film written to appeal to young children. Older children already go to MCU, DCEU, and other superhero films.
From past Deadline Articles:
Into the Spider-verse
As we mentioned previously, exit demos for Spider-Verse were 67% non-families, with men 25+ repping 41% of moviegoers, followed by men under 25 at 26%. Both enjoyed the movie with men under 25 giving it 96% and men over 25 a 91% positive score. Boys under 12 outnumbered girls 70% to 30% in turnout. Diversity demos were 43% Caucasian, 21% Hispanic, 16% African American and 15% Asian. Friday's number for Spider-Verse includes last weekend's money from paid sneaks.
Spider-man Homecoming
There was always the notion that this Spider-Man would skew younger and ComScore/Screen Engine's PostTrak supports that showing 43% under 18 in updated audience polls. Since Friday, the under 25 crowd swelled with females moving from 18% to 22%, the third best demo for Homecoming after guys under 25 (35%), men over 25 (24%) and ahead of women 25+ (19%).
...
Forty-nine percent of Homecoming's audience was Caucasian, 24% Hispanic, 13% African American while 10% were Asian.
I can't find family stats for Homecoming, but there were more young people going to that than Spider-verse by percentage.
Either way, I don't think that Spider-verse is hitting an audience missed by the live action films, and it is going to miss most of the overseas audience because Asia and a few other places don't find animated heroes as compelling. The live action superhero slate isn't so busy that you couldn't cram 1-2 more on a year. So again, the animated films are going to have to justify their existence. At least in the case of Spider-verse, the film is going to be SPA's first real taste at critical acclaim and possible awards season trophies. That shouldn't matter that much, but Hollywood still likes its awards. I think that the domestic take will end up justifying the sequel anyhow, even if overseas is sub 200M, but if it was borderline, the acclaim will probably help.
As for Lego Batman, 136M overseas is pretty poor. The fact that the original Lego Movie didn't do that well overseas doesn't change things. Those overseas grosses are comparable to what you would expect from an animated film that earned $50-100M domestic. Ferdinand made $211M overseas.