The business model for custom premium air rifles didn't work in the 1980s either.
Affordable Jap scopes meant that many shooters wanted to reach further than just the farmyard. All because they could see further
The HW35 could be tuned to get out to 35m which was progress. A lot of trial and error by hobbyists was done on the HW35 to make it reach the longer range. Most HW35s couldn't do it out of the box.
A market grew so a few shed tuners got so busy that they become small businesses. Both super premium walnut rifles and for knockdown target tac drivers. But these businesses barely got away from the shed. A couple went big: Theoben, Daystate, Air Arms.... Some of the new ventures didn't last long: Sterling, Park Rifles. BSA and Webley struggled to change with the times. BSF failed. HW80 and the HW77 saved one company.
And then PCPs arrived that can do 35m plus, and makes that easy. Now 200m plus and knock over an Elk.
If the UK was The driver of progress in the 1980s, the USA is now. Innovation coming from many countries though the UK is at the forefront of much.
There is room for springers, gas rams even, but it will be PCP that is the future. Manufacturers will support springers so long as they sell. Home shed tuners, hobbyists or small scale professional, will continue, but as for the latter I suspect they will always struggle as did those in the 1980s.
All done because air rifle shooting is fun and there is something for everyone.