Army made a tank it doesn't need and can't use. Now it's figuring out what to do

The 1st attempt to replace the Sheridan, - the M8 Armored Gun System[0] had a similar problem - too heavy to be transported / airdropped by a C-130.

[0] https://en.wikipedia.org/wiki/M8_armored_gun_system

Much like the US Navy's LCS, both Independence and Freedom classes:

https://en.wikipedia.org/wiki/Littoral_combat_ship

Good grief!