>>530546937
I'd say yes, since umas would be just as vulnerable to artillery, air and all the things that squish normal infantry.
The first tanks were one of several solutions for the deadlock of trench warfare, being able to resist machineguns and shrapnel while rolling through barbed wire.

Moving forward, the prospects for using uma as a tank substitute get even more bleak as armies mechanize and the tank matures in line with modern maneuver warfare, as the rate of advance possible outpaces what even umas are capable of sustaining. As a unit of operational maneuver, the tank was and remains simply unmatched in its niche.

Towed direct fire cannons did exist and were effective on the defense and as a way to attach dedicated firepower to infantry units, but they were always a weapon of expedience, since shitting out a cannon is far easier than building a whole vehicle. More than other things, these were positively fucked if they were caught out of position. Modern weapon squads fulfill much of the same role.

Umas in modern warfare would be much better utilized as a precision tool (special forces) than getting attrited just the same as part of the regular mass of the army.