I highly encourage anyone who has not yet watched the video linked in OP to watch it. It is top players' experience that pathfinder spam is the strongest strat to deal with. Gachi's comments were on point and Esxile's point of view, despite being on the whiny side, to some extent I agree with it, but I think the issue lies in USF weapon upgrades being strong en masse in late-game and unaffordable in early-game, which affects Riflemen performance.
I agree with Shadowlink's statement that pfusilier spam is braindead as well, but it's not quite as strong as pathfinder spam and it deserves a separate topic.
You touch something different than what I mean in this topic. You don't reach ISU-level long games when you play vs competent pathfinder spammers, because they win even sooner than that. I don't mean meta being annoying, I mean 1 strategy being undeniably and disgustingly the strongest way to play a faction in 2v2.
Also who doesn't veto Rails and Metal deserves it
It all depends on the level of communication in the opposing team. If they are both braindead but know each other/talk during the match/cover each other you are 100% fucked if you play with random, even if you are top 500 material.
Same of course can be said about any kind of spam really: pfussies spam, JLI spam (boy is that cancerous), (insert stock british medium tank) spam, etc etc etc