Exactly.
There are aloes questions as to whether Peter was in Rome, died in Rome or was buried in Rome. The donation of Constantine supposedly establishing the primacy of the Roman Church above all others is also very suspect.
Anything that cannot be supported by the Bible is simply a part of “Tradition”. Most of the theology regarding Mary has been invented (Mary as the co-redeemer as if this was needed) and confirmed by “infallible” Popes as unquestioned dogma.
Just to clarify, Mary as “co-redeemer” is not Church dogma (Church teaching). Some people advocate for it, as is their right, as it is not objectionable, but no Catholic is required by the Faith to adhere specifically to the idea of co-redeemer.
FYI, there are only 4 Marian dogmas, they are:
Immaculate Conception
Virgin Birth (”perpetual virginity”)
Assumption
Theotokos