I can understand the use for “bass player” in english. In my mother tongue, however, it would sound very weird to call someone a “tocador (player/toucher - yeh -) de (of) baixo (bass)”.
It’s rather common to say “x toca baixo” (x plays the bass) or “eu toco baixo” (I play the bass) instead of “sou baixista” (I’m a bassist). When referring to a band’s bassist, it’s more common to call them “baixistas” (bassists)
Below is the definition of the suffix -ist from Merriam Webster
1a : one that performs a (specified) actioncycl ist : one that makes or produces a (specified) thing - novelist
b : one that plays a (specified) musical instrument - harpist
c : one that operates a (specified) mechanical instrument or contrivance - automobilist