Once I read, that without the Nazi Germany attacking Russia, Hitler would have had more than enough troops to stop/prevent D-day, making the reconquest of Europe by the allies impossible (Remember the Soviet Union would have been still neutral with Germany, and they did a lot of work in the liberation of Europe). Even more it was suggested the possibly of a cold war between the Soviet Union and the Nazi Germany. Well anyways too much off topic.
On topic mode (activated)

For you to know, the tank concept, has been several times considered obsolete by modern armies, the most serious one, was with the appearance of the attack helicopter; helicopters eat tanks, they still do so today, they're the perfect tank predator. What I mean, if games were to follow reality, you'll only see helicopter rushes , and if you were going to make a mod based in TS "realistic", both mechs, and tanks would be obsolete against the firepower of Orcas, which are highly fast and maneuverable helicopters. So in short my point is, you can't have reality in a game, specially this game, if you don't want to severally cripple it's origin.
I agree that mechs are really an impractical design, we might never see a warmech (at least in planetary surface), but they're a part of the legacy of TS, even TD (if you have seen the concept art), also they're quite cool machines.
Finally, on a side note, I would support no new mechs in this mod, but not for the impractical design reason, but for the animation; voxel mechs are the ugliest thing ever made, specially that hideous mammoth mk. II