The modern models and digital processing and solid state gear has likewise surpassed audio reproduction. The reason the B-15 sounds subjectively great is because it reminds us of the sounds we grew up with. But no young players are looking for that.
I disagree that no young players are looking for that. A buddy of mine is a sound engineer at a well regarded recording studio in the Chicago area and they're constantly using their B-15s to record bass, precisely because young artists are asking for it.
Modern, digital gear can do some amazing things that vintage gear can't even begin to approach. Plus, it's reliable and affordable.
I got started in multitrack recording in the mid 80s and started adding digital gear in the mid 90s. By the year 2000, I had gone completely over to digital with the exception of my tube driven bass amp.
I could use plug ins and emulators if I wanted to and get 80% of the way to where I want to be, tone wise, but there's something special about the tone of a tube amp recorded through a speaker cabinet that simply cannot be equalled by digital processing.
But, given the rate of progress in the field, I suspect that within another 10 years, that will no longer be true.