The tanks were and are fantastic. The problem is they were designed to be in Germany where they’d rush to the Fulda Gap and stop the Soviet armor. They were never intended to be shipped or air dropped into a combat zone. Yes, they require a sophisticated test and repair facility. There are line replicable items, meaning battle line replicable and then there are depot replicable items. The tanks have a mean time between failure of about an hour. So, they require a lot of spares, and they are much harder to diagnose than your car. (By the way I worked on a line replaceable assembly the size of two packs of cigarettes. We charged $40000 for it. One honking relay and some thick resistors. Forty thousand dollars.)
As for why the Ukrainians don’t have them yet. We’ll have to build the export model as there are probably none sitting around. The export model has different armor and may have a different set of internals and software. It probably takes a year to train depot personnel and a few months to train crews to do maintenance and then the crews have to learn to fight the tank in combined arms. The tank by itself is more vulnerable than a tank surrounded by infantry and support vehicles.
The logistics of supporting Abrams and F16’s is complex, expensive and easily hit by Russian bombs and missiles. There’s no place in Ukraine where it would be safe and secure enough to have a repair depot. If Russia was losing badly and they blamed the tanks or F16’s then they might attack the repair depots that are currently in foreign countries repairing the old Russian hardware that has been seized.
whaaaat?
So if the Russians or Chinese take out a repair/parts depot, the tanks all grind to a halt within a few hours?