All of the great bass players that I know have a lot of basses. But they have 1 or 2 basses that they play mostly. I think if you are a 'developing' bass player you should considering focusing on getting better more than going through and owning a lot of basses.
As for me, I've been playing custom made basses since the 90s. And for some reason I was smart enough then to use 'common' physical specs that would give my custom basses similar 'feels'. All of my 'main' gigging basses have 5 strings, 35" scale, 19mm spacing at the bridge and a thin neck profile. I've found that when I pick up bass that doesn't have these specs it's not as comfortable in my hand. It doesn't mean that I won't play that bass well. A lot of 4 string basses has 19mm spacing. And I can adjust to 34" scale easy. For me the biggest obstacles is significantly tighter string spacing and thick neck profiles. Even my 7 string MBass has 19mm bridge spacing so even though the neck is wide, the bass is easy for me to play because the amount of space between the strings is what I'm used to and the profile of the neck is thin.
Having said all of that,...
If a person is in the beginning stages of bass playing its probably a good idea to get comfortable with one bass.
Everyone is different. Some of us adjust to things easier than others. And as I teacher I know that none of us do things the same. We all are different and are affected by things differently.