I think we're discussing two different types of beast here. The likes of Devonish, Eldridge Pope and so on were caught between the really big boys (back in the day the likes of Whitbread and Courage) and the smaller artisan brewers. The medium ones were producing not particularly brilliant beer and doing it without the real benefits of scale.
What seems to be happening now is that the first generation of very small brewers is coming to an end, in many cases due to retirement. We've lost Cottage and RCH round here for that reason and Ringwood sold out to Marton's when the founder wanted to retire.
In the case of Yeovil, I don't think that is the case. I think they have hit financial issues due to the pandemic. But I suspect I will never find out.