SomethingAwful goons have hit a fairly good point on why the most annoying redditors and youtubers people keep declaring tanks "obsolete":
when you look at recent (~30 years) NATO wars, tanks appear indestructible, so any war where they're lost in numbers seems to signal their obsolescence.
Except, as it's rightly pointed out here, nothing that any army produces is indestructible. Tanks, just like anything else, can and will be blown up.
If you look at World War 2, they can be blown up in large numbers. Notably, nobody walked away from that war thinking "gee, tanks sure suck." Soviets lost 80,000 tanks during the war. Then they designed the T-55, 100,000 of which were produced during the Cold War and which lovably proved the German idea of "we should only make lightly armored tanks now, meaningful protection is now unachievable" wrong, pantsing Leopard 1.
Goons also mentioned Arab-Israeli wars, which saw the debut of the ATGM... which didn't lead to tanks becoming obsolete (though a lot of people, especially the Soviets, became really enamored with the idea of putting ATGMs on tanks).
Another thing is that tanks were never meant to be used alone. Even Hanz Guderian writing in "Achtung, Panzer" said, very clearly, that a tank is a part of a combined arms assault, with tanks, infantry, artillery, and air doing their own in this concert. Sure, tanks be wicked killy in open terrain where their mobility and gun can do the most harm, but wars aren't exactly fought on featureless plains.
Lastly, anything less than a tank is more vulnerable to anything that can kill a tank than an actual tanks. ATGMs? Boy, IFVs and APCs don't even potentially have the armor to eat one of those, plus, if you catch one with passengers, that's 12 people dead. Artillery? Non-tanks have less armor, so they're even more vulnerable to nearby hits. Air? Read back on artillery. Tank guns? They're the one thing that no active protection system can't defeat yet, so any "light vehicle with a big gun and APS" design that some wankers are suggesting will die to a tank.
The only way to make the argument here is at which point it becomes more economical to lose more lighter vehicles and infantry than a single tank.
And considering that Ukrainians are now begging everyone and anyone (even those German assholes) for MORE TANKS, shit, the tank seems like it's here to stay.
