Life is to short to worry about what might or might not happen in the future, especially if it is beyond our control.
Quite right.
Part of my motivation to explore electric bikes was to plan for the future, where one does not know because of advanced age or other matters, driving might not be permitted. Meddling with my ability to replace bits of my assisted bike, is not going to be well received by me. I will make my own batteries if I have to. As long as they don't outlaw sale of cells...... I'd put nothing past the meddling nanny state lot. They are found in all parties, but are more common in some.
It would be FAR FAR better to use education as the mechanism to reduce fires (not that they are that common considering the numbers of ebikes and other battery vehicles. However - in my experience, the lunatic end of the population are immune to advice of any kind and can be found all over the Internet advocating absolute stupidity. Proper analysis should be carried out to discover exactly what kind of batteries have gone into melt down and what use they were put to.
My bet is that crazy things will have been done to most of them.
Attention to BMS quality would be a good thing. We all rely on that inexpensive little board to keep things safe. For such a cheap item, we may be over trusting them.