Sky's the limit. If you do get a 30K Alembic or 20K Fodera, those prices won't prevent you from playing the bass out of tune or clanging on the frets. Actually with Alembic's complicated pre or Fodera's Pope preamp controls turned to the extremes, you probably will have some unpleasant tones as well.
So let's take it down a notch and get yourself a passive Lull or Fender custom shop (I don't know how much they are now 4K - 6K? ), you can still make them sound bad. My point is the most expensive bass will not prevent you from making it sound bad. Now setup that Alembic with wacky intonation, high or buzzy action and bad strings, it will sound bad and be very hard to play as well.
It's not like - Hey I want to learn to drive a car. You can learn to drive on a 200K Benz also. There is no need to start on a Camry or Kia. But if you get a race spec'd not road legal rally or NASCAR which cost more than the Benz, you will probably wreck it very quick. It's not the money but you can get injured or die and take even someone down with you as well.
Bass guitars, well set up bass guitars should be easy to play whether you are a beginner or a pro. This concept of beginner guitars serves only one purpose. If that consumer looses interest they will only loose so much money. That will be the First Act music category. Anything after that, nowadays is actually a decent instrument.
I would advice that you take someone who is already an experienced bass player when buying the bass and set aside 50 to 100 or whatever it is in your locale for a decent setup. Nowadays 400 can get you far that the bass will probably even serve you gigging.
My assumption here is that the majority of us here, have too many nice instruments (includes me) not actively gigging or not depending on gigging to survive because we have other sources of income. Many have basses and amps that are pro/touring level and nothing says we can't even if we leave this earth not having jammed or played with anyone else. Many play for their owne enjoyment alone and nothing wrong with that.
Of course just by the nature of this forum, if you start a thread about a 20K Fodera Monarch and you do not know where the E string is, it will raise some eyebrows and you will get flogged by some.