You can slap six Javelins on a pickup truck and ruin a whole tank platoon's day. Fair. So why do we have Abrams, again?
Because, my child, one day you will come in contact with a minefield. And behind that minefield will be three sets of barbed wire, and behind that barbed wire will be a 20-meter tank ditch, and behind that tank ditch will be more barbed wire, and behind that barbed wire will be a secondary minefield. You will be staring directly at half a kilometer of complex obstacles. You will need to cross those obstacles.
And on that day, you will look to the heavens and cry out for a 70-ton tracked vehicle with four solid feet of armor and a 1500 horsepower engine, a vehicle equipped with anti-minefield breach capabilities, stocked with gap-crossing bridge capabilities, and armed with a 120mm direct-fire cannon to protect those breaching assets.
And I will look down and whisper, "do all of that with your M113 chassis family of vehicles, bitch"
That is why we have 70-ton tanks. Because sometimes, you need a land battleship. We figured that out in 1914.