Battlegrounds match ups lately

DrWooper

I'm usually not one to repeat stuff out loud but please can someone address this?

I've been in plat 4 for about a week now, everyday I try to play Battlegrounds to progress (using energy) but I keep facing valiants, legend titles and high tier paragons

I myself am a throne breaker but I'm only missing one r4 to become paragon.

Is the matchmaking based on my roster or my progression title? Because I only have one 7 star r1 and 6 stars r3 and r4...so I find it hard to compete with these opponents l