I agree a conservatory or university degree in accordion is only a starting point for a professional music career.
And as you truly say, not even necessary if the player has the talent and the audience.
Large majority of the accordion audiences and accordionists will prefer Stradella bass popular music.
However, professional training of future accordion teachers can not ignore classical music and modern music, and so free bass convertor instruments are indispensable.
Conservatory trained accordionists can and do play a large variety of music genres, including all sorts of popular music accordion styles.
The question is, can the accordion community, outside the conservatories, accept the accordion as a music instrument for classical music??
That still ( after so many decades the free bass and convertor has been around ) can pose a problem in the mindsetting of many accordionists.
Not because of the accordion as a music instrument, but because they dislike or hate classical music and modern/avant-garde music.
The free bass or convertor accordion is not the cause of these ( a pity
sometimes seperated worlds between popular music and "serious" music in the heads of many accordionists.
You could find countless pop/rock guitar or pop/jazz/rock piano players that also dislike classical music, but I don't hear these people blaming it on the guitar or the piano as music instruments.
Lets not mix up the love or dislike of music genres/styles with music instruments.
One sole instrument can be a tool for playing in different styles/genres.
The inconvenient truth still is the conservatory accordion students learn all music genres on the accordion.
But many accordionists want to keep the accordion held in a cage of popular music only, because they just can't stand or listen classical music...
In fact it is the conservatory accordion students that have a more open mindsetting regarding the different music genres being played on the boxes.
(I accept conservatory accordion education has the focus on free bass study, but, "hey, what did you expect ?" , you don't see trumpet, piano, guitar, violin students at conservatories spending all day playing popular music. They have to cover all the music history timeline, thus focusing on classical and old music in the first place).