Plenty of older games had tech paths though. Command and Conquer, for example. Any game with production structures, really. The difference here is most people in this game completely neglect building "lower tier" units and structures.
There's plenty of this in Coh2, OKW is full of it. That's why the Luchs comes from the panzer command and the jagdpanzer comes from the medic command. It's why the Puma is in mechanized and why the raketenwerfer can be built from HQ. Relic does actually plan this stuff fairly well. (Atleast in this game they did. DoW2 was half-assed with T1 based anti tank)
For Soviets the way this worked was thus:
T1 is the only structure with no AT potential. But it was also primarily early game stuff, so that's no surprise. Even so, Satchel charges were an option and do good AT damage if you can immobilize them first with engine damage. (At grenades?) That said, you generally wanted to either go T2 or T4 after going T1 for AT options like the ATG or Su85.
T2 had AT guns, nuff said.
T3 had T-34's which had Ram which worked well at disabling enemy vehicles for your other AT to kill them. (This got neutered though.)
T4 had Su76 for lighter vehicles and SU85 for late game tank destroyer.
I'm emphasizing AT because that's generally the thing everyone needs in this game. But vehicle wise t3 offered a light tank and a medium tank (and at one point the katyusha, but that got swapped with the halftrack because 4v4 scrubs didn't understand how "non linear" teching worked and thought halftrack came too late to be useful.) T4 had the halftrack for anti infantry and support, SU76 with some AI potential.
HQ had molotovs for anti garrison, penals had satchel charge for antibuilding, AT gun and su76 both had barrage for similar purposes. etc. There's actually a lot of such overlap, and for a reason.
In other words, they had all their bases covered and if you wanted to do risky tech like T1 to T4 you had stop gap options in the form of ATG, mines and guard rifles. Any sort of safe tech included T2 for AT guns. (Which paired nicely with shock troops)
I can understand why people wouldn't like this sort of tech structure, but it's a shame Relic bent over and homogenized it.
i meant that teching in older games was more limited, not that it was non-existent. there was a LOT of teching in ensemble's games as a tech advantage was the best way to win. of the newer RTS games i've played, most of them are more focused on micro/macro but they also have more unit variety instead of 4 different versions of each unit, each version being slightly better than the old one.
the first two factions are really the ones that have significant overlap, although the soviets had issues with t1/t3 not having anything to really deal with V/VIs and not having any fallbacks if their 34/76 was destroyed. i think their design worked a lot better in 1v1s in team games though because it's harder to get run over by multiple vehicles in smaller games. in team games soviets had a very hard time against tanks if they didn't get the su-85 out. they're much better now AT wise with su-76 in t3. even with the old design though, t1/t3 or t1/t4 still worked if you gained enough momentum to get a fuel advantage. the part i didn't like was that it was pretty much over if you didn't.
USF has very little overlap, apart from the m2 and m15 both suppressing and the m8 basically being a packhowitzer on tracks. OKW has overlap in their AT vehicles (jpIV/puma/V) although each is weaker/stronger then the others and has different utility. there's also overlap with the 251/8 and luchs although it has a similar dicotamy to the jpIV/puma/V where by the luchs is much better in general than the flaktrack; it's effectively a replacement unit.
i wouldn't have any issue with the old soviet tech structure if they had a core that included a decent AT gun and a decent generalist medium vehicle. their first two tiers worked fine with t0, they only ran into issues against heavier tanks because of lackluster AT options. OKH never had that issue because they always have access to pak40s and schrecks (both of which are very good, unlike the PTRS) and could then get stugs or IVs or Vs, all of which were also very solid units.
when core stuff is missing, like suppression when going t1 or AT guns with t1/t3, you can end up not having counter play options to things the enemy builds and i don't enjoy that. USF has a similar issue in dealing with MGs early on certain maps as they have to rely on smoke which is both expensive and not very productive.