Well it's either they spent money, through promo codes or got them through ECRs (Event Crate Rushes). Yes, legendary mechs are comparatively better - there is only one epic mech that can compete with legendary mechs from my perspective.

there are a lot of non legendary and not even epic mechs that can compete with legendaries. The matchup and weapons matter most. Use full stars Vortex with berserkers against full stars guardian with fragment guns at a 30m distance i think i would prefer to be guardian mech in this situation. Epic mechs have a lot more space to wiggle especially depends on matchup of weapons. It depends on skills and knowledge too, if you know that behind the wall is guardian with fragment guns, i would stay back if i was a vortex with berserkers.. and i could win if i could keep that distance, but if there is a time limit you would eventually have to come to that wall and good luck to both then. Im not even mentioning lancer, which is common, a lancer with compound beam could kill wortex with revokers, because it would keep distance. So its all nonesense you are talking here both of you.