Yes and no but depending on people at play in that moment. As higher the amount of people playing, the closer to the rank and stars is more pronounce. As the limited player, the tendency is to search for higher and sometimes goes into the weaker.
In my low rank test at R7 it goes toward the average of stars accumulated by rank. Tested countless time and still testing with HP, modules configurations, weapons all simulating closer HP and deficiencies set on purpose to win or lose. The check is to verify the lagging on modules and type of mech for phys, heat, energy and hybrid.
When I play at R7 higher stars, the number of players against at R5 it goes to 40% and sometimes goes 50 plus adding R4 even R3 and start to become a problem giving R2 players. My mechs set ups are pure R7 but even giving wins to players asking, the match maker set me up with strong opponents pushing me down to R9 even have been R10. Last season I was against the wall R9 zero stars with the same mechs and the game still setting me up against R7 and R6 and of course because the low stars then go into R10 match selections but are too weak against my R7 mechs even so trying to go up does punish 2 ranks with possibilities to win but setting me up with same players that push me down losing.
At higher ranks let say R3-R2 the tendency is that R3 fight R3 because the number of players is in R3 and R4-R5 but crossing half starts on R3 the R2-R1 are coming to hunt. I have been on test mode for over 2 years.
I stay on R5 or R4 or else on purpose checking all the time according to my mood of the season. Also, regardless players and type of mechs around, some accounts are set to the worse can get. I have played other players accounts for seasons, and I can say can get R1 really easy with same mechs set ups as mine and when I play mine at the same time, it is a nightmare match to lose on position, start and floor mats plus the type of mech. It is not about performance during the fight, it is the type of mechs that inflict the damage fight after fight not a balanced match crushing 5 losses to have to move up.
Win or lose I do not care, what I like to see is the selection and play in ways that average player will do making mistakes risking the attack to see results on damage.