Why nobody built them in WW2 ?
They seem to be the ideal weapon for the Axis powers since they allow to land an armoured force on an undefended part of the enemy coast without having air or naval superiority.

>>63932213 (OP)
Look what I made with my legos, mum!

For the same reason why transport submarines are not a thing and its use in ww2 was inconsequential: really high costs for marginal gain

>>63932249
Not at all. Transport submarines were in high demand on the Axis side. They were just introduced too late in the war to be effective.
https://www.navypedia.org/ships/italy/it_ss_romolo.htm

In an amphibious operation carried out under overwhelming air and naval superiority, there is no need for the ability to dive and survive enemy attacks.
A surprise landing without the prospect of continuous supplies is reckless.

So you manage to land a handful of tanks, a hundred men, and a few trucks worth of supplies on the enemy shores. Now what?
They will get absolutely fucked by any sort of national guard.

>>63932213 (OP)
The Soviets considered making them during the Cold War as well to invade Iceland. There’s really just no point landing a couple hundred men and tanks just for them to get gunned down

>>63932213 (OP)
Compare the cost and complexety of this to a dozen gliders.

>>63932213 (OP)
>Land troops while you don't have air superiority
>They get fucked by enemy aircraft because they have air superiority