Western armies have more infantry, which is why the armies are big. The Russians are replacing their infantry with heavy weapons. Like the newest one is the BMPT Terminator, which is meant to replace a BMP-2 and its 7 troops. The BMPT needs a crew of 5, whereas a BMP-2 is packed with 10, so they cut down their manpower requirements by half with slightly higher initial costs.
The manpower required for logistics isn't a lot. A lot of the increase in efficiency has more to do with transportation than manpower.
An Abrams BCT has 90 tanks, 150 Bradleys and 45 M113s. A Bradley carries 6 troops and the M113 carries, say, 12. So the infantry support is about 1500. Otoh, 3 tank BTGs are needed for 90 tanks, and they are supported by a total of just 30 IFVs carrying 7 troops each, that's 210 troops. A ratio of well over 7:1. This is where the Russians separate themselves from Western armies.
It's the Russians that are aiming for more automation on the ground than anyone else, 'cause of their population problems. Future Russian units could become even smaller with the addition of new weapons like the BMPT.
In any case, precision weapons are mainly carried by artillery. Compared to an Abrams unit, the 3 BTGs would have just 2x the amount of artillery. So, at worst, the Russian unit will just need an extra guy for each gun or the crews will have to work a little bit harder. If you work fast enough, 3 guys can load a howitzer with some 40 shells in a matter of minutes. So you are exaggerating the problem.
As of today, the jury's still out. We will know only once they start mass production. They plan on building 100 Felons a year. So that speaks volumes about their confidence in it. They plan on starting off with 24 a year initially. No clue about the Armata yet, let's see what they decide in a year or two.