Being able to directly support infantry and their IFV/APC on the frontline?

I wonder if the new "tank" will be a wheeled SPG that can fire hull down and has an APS system. Or it could be something like BTR 4 with its auto cannon, being able to carry some infantry, add APS to that and you have a lethal combo.

There is also a lot of overselling of infantry support. Stugna or Javelin can kill T80 from 4km away, what use is dismounted infantryman there?

Well they can carry their own Stugna or Javelin. Isn't that an argument for more dismounted infantry, not less?

Warning: combat footage, people die...

A T-72 is both easy to detect and easy to kill for someone with a Javelin, while the Javelin-man is hard to detect and non-trival to kill (at range) with the T-72.

The arms race between protective equiment (armor, shields, etc) and anti-armor weapons has been going on for over a thousand years, arguably longer (like when Roman pila would get stuck in enemy sheilds, making the shields useless, even if the pilum didn't kill the enemy soldier).

In our current age, the previous generation of tanks has been made obsolete by ATGM, just like Cuirassiers were obsolete at the outbreak of WW1 and WW1 tanks were obsolete at the outbreak of WW2.

Modern tanks with state-of-the art sensors and APS are much better protected against ATGM's. While still not the ideal platform for use against anti-tank weapons, at least they don't get slaughtered on first contact. If the enemy has a high concentration of ATGM armed infantry in an area, it's probably better to take them out with infantry, artillery and/or aircraft. Given the cost of ATGM's, this is cost-efficient. And if the ATGM's are spread out, a tank formation with good protection systems can affort to smash through, even if it comes at the cost of a few casualties, to maintain momentum.