It has been about 5 years since I even stopped playing. I started playing during closed beta and my most active time was around 2014 or something along those lines, so your mileage may vary, especially today.
The ELC has tissue paper for armor, still I had my fair share of games where my shots just bounced off or only managed to detrack them without doing damage for no discernable reason, even when they got hit on a very flat angle dead fucking center. The tank wasn't unkillable, but it managed to take abuse that made my heavy tank on a similar tier blush.
The ELC was not an automatic "I win this round" tank either, but it was bullshit on tracks at times.
The tank also might have downsides like the limited gun angles, but nothing to really balance how strong it was in other regards. If they made it get bogged down in mud or whatever at some later point, that's certainly nice, but that was not a big deal when I was still playing (and ELC players merely avoided such terrain).
@Corn Flakes also mentioned the E-25, now that fucker was even worse iirc.
"No one would be playing anything else" ... unless, of course, you're like me who plays Germans exclusively for autistic reasons (so no slav bias for me), or you're stuck on a tier before you get to the good shit, or you have to play low-tier tanks to afford repairs and upgrades for your high-tier tanks (and end up with tanks that are clearly put into way too low a tier in the other team) or you don't want to shell out 50 bucks for a tank that might be decent for some time before they nerf it cause you're a poorfag, don't want to throw even more money at the game then you already do and so on.
My point being that there are many reasons not to play the most OP things ranging from tastes in tank designs (when it comes to regular tanks) to mere monetary aspects (when it comes to premium tanks). What good is it if the soviet high tier heavy tank is the best thing since sliced bread if I already poured dozens, if not hundreds, of hours into grinding German tanks by the time I find out how utterly broken that other tank might be? Especially when the annoyance of OP tanks is something that accumulates over time. It's much more likely to drop the game at that point - and a lot of people did pick certain nations based on how strong their tanks are.
Some tanks are bound to be better than others. Still some tanks are way too good at what they do compared to similar ones - especially considering their tier. KV-2 was a mere turret-upgrade of the KV-1 at some very early point, for instance. At tier 4 if memory serves correctly. Of course, that was also the time when my tier 3 (? I think) Luchs ran together with a tier 10 Maus in the same team every once in a while, so that issue hasn't been relevant in almost 10 years - but it was a problem at some point.
But since I'm on a rant here:
The matchmaking was a thing of wonders, too.
I stopped playing when the matchmaking started to do really weird shit that made a large number of matches simply unwinable by default.
The way matchmaking was supposed to work was to put together 2 teams with somewhat equal tanks (ie: mix of lights, mediums, heavies, TDs and Arty of the same range of tiers) but the algorithm had some blatant bias shit going on here and there. I lost count how many matches I had where my team was simply in no position to win whatsoever due to team composition alone and you could tell on the loading screen there was simply no way to avoid a crushing defeat.
In many instances, we were out-tiered by our enemies in such an obvious manner that it simply could not have happened on accident.
Like our best (sometimes only!) heavy tank was -say- a tier 5 (not even fully equipped), while the enemy had 3 or 4 heavies from tier 6 and 7 and nothing about the rest of the team made up for that imbalance either. You'd maybe expect to have high tier mediums or TDs or whatever to make up for it, but nope. A team with less heavies, worse heavies and everything else either also falls short or (at best) tallies up equal to the rest of the other side.
I had a couple games where half the hostile team was high-tier heavies and we had not a single heavy in our team at all with predictable results.
I didn't mind the slav bias or the occasional premium tank here and there, but that just fucking broke me. It's one thing fighting an uphill battle, but it's an entirely different one to realize you're just a target, not meant to put up much of a fight, in a shooting gallery for the paying customer. And the longer this game is around, the more premium tanks are around, too.
