Mecha was a 1960s-1980s war-inspired fascination that maybe, if anything, we should be surprised at the longevity of. We haven't really been getting that many giant robots or pilotable mechs in popular media outside of Japanese animation.

Mecha is never going to disappear. Mecha are great for toy sales.

I always felt like the big explosion was the 80s, not to say the 70s was unremarkable and the 90s just had a lot of really good stuff like turn A, Eva (I dislike it) and King of braves GGG

There is an upcoming Mech movie Atlas, starring Jennifer Lopez with a heavy Titanfall vibe.

Patlabor wasn’t war-inspired; you might enjoy it’s contrast to gundam-type mecha stories. The Labors represent the rise of technological power that can be employed by a single person and all the effects that can have.

We got Gundam Witch last year :)

And Gundam SEED Freedom this January.

Yep. The last mainstream mecha anime were Darling in the FranXX (2018)[1] and 86 (2021)[2]. Anime like Gundam are much more niche if you compare the amount of MAL users.

[1]https://myanimelist.net/anime/35849/Darling_in_the_FranXX

[2]https://myanimelist.net/anime/41457/86

Attack on Titan is for all intents and purposes a mecha, and one of the most mainstream anime of recent memory.

It has mecha elements, as well as steampunk and magic elements too.

Other than their kits, everything else they operate is very standard WW1-esque tech.

Gundam, the niche that does 100 billion yen in revenue per year.

The toys are appealing even to children that never saw the anime.

Actually I wouldn't let my kids watch it until they were at least 13 or so, maybe more depending on the child. A lot of war and mass-scale death there, and frankly, a lot of adoration for fascism - the space nazis turn out to be right.

Wing (and, by extension, 00) was a fine watch at 10, and G probably would have been, too. They're considerably less fraught in both iconography and philosophy than some of the other series, and quite a bit more hammy. The Build Fighters/Divers series are great, too. Stay far away from AGE, though; cutesy stylings because it was intended to exist alongside series like Yokai Watch, but it ended up being quite problematic.

Anime and Fascism really do seem to walk hand-in-hand a lot.

Even my beloved Frieren has an unnatural dehumanistic streak against Demons who exhibit intelligence and personalities, which she explains away as mere mimicry, despite the fact that she has learned magic from them.

I guess I know which side of the AI debate she rests on.

Mecha fandom doesn't necessarily cross over with anime fandom (even though the former is arguably the origin of the latter). I find that there's more crossover with hobbyists (plastic models), military fandom, and gamers. Gundam is almost it's own thing (to Sunrise's simultaneous satisfaction and chagrin), and the Site Which Shall Not Be Named split a Mecha board off of the Anime board almost 2 decades ago. I don't know that the fandom will be represented on MAL, which is itself a niche service for the wider anime-watching community.

Suffice it to say, the multiple life-scale Gundam statues that have been put up/dismantled over the past few years speak to its enduring popularity. I will say that there haven't been as many non-Gundam mecha anime as there were in the 2010s. We did get G-Witch and Bravern last year, and Hathaway on Netflix in 2021. And, as someone said, AOT is essentially Meat Gundam.

EDIT: Also, I don't know that I'd even call 86 mainstream. It felt like it actually got way less recognition than it should have.

I thought EightySix was pretty good (2021-3)

Last season had Yûki Bakuhatsu Bang Bravern, SYNDUALITY and Gundam SEED FREEDOM, this season has Shinkalion and next season has Grendizer U. "Disappeared" seems like a strong word.

I watched Shinkalion purely out of desperation and was pleasantly surprised despite being a show for kids and having "terrible graphics".

And yeah there's not much mainstream, but you always get some Mazinger spinoff, some Gundam and other "minor" stuff. The genre is definitely not popular but it's alive.

Super Robot Taisen is also still ongoing, and while it's not a show (although it's been adapted a few times) it's a good way to find stuff that might have escaped your radar. And the originals can help quench the thirst for new cool robots with flashy moves. Lately they have been adding "never animated" stuff like Mazinger ZERO, GaoGaiGar Vs. Betterman and Getter Devolution which is nice too.

While I'd like to blame the metastasization of the narou-kei LN adaptation, I think the real reason is the same as why Sci Fi has largely disappeared from visual media in general outside of hangers on from legacy franchises. People have stopped believing in the future.