While you view the QCATS et al as as valiantly sticking it out during the rough times when their Caldari counter parts ran for the hills; I view them as fish that’ve grown too big for a little pond but refuses to head for the ocean. As I see it, those other groups didn’t abandon FW, they dutifully moved on to bigger challenges. To me, sticking around to feed on young, disorganized prey because they enjoy being the baddest thing in the spawning pool isn’t to be lauded.
This isn't a theme park MMO, where you move to different areas where you gain in level. This is the sandbox and the endgame is what you make of it. By and large, our ranks are made up of people who prefer small-gang combat and the solo opportunities that low-security space offers. FW provides the quick access to PvP with a free wardec and plentiful WTs that nullsec does not.
Keep in mind that many of our veterans
have tried nullsec and found it not to their liking. SOTF went full nullsec before they decided it was not for them. And who could blame them? After years of nonstop action, they ended up grappling with boring CTAs (sitting for hours in ship waiting for the call, only to be blueballed and then having to grind structures for more hours). Nullsec is a different lifestyle than low-sec. Viewing FW as a stepping stone or as a training ground for 'larger ponds' is a paternalistic and condescending view.
The idea that CCP was treating FW as a 'stepping stone' into nullsec was one of the major gripes of the population at large when Hans was elected. And part of his platform was going to CCP to change that attitude and make it clear that many in FW see it as their preferred end-game. This was a concern that was shared by many entities across different militias.
And it isn't the Caldari militia that are the only regular opponents of organized cap-dropping groups such as SOTF and SPDR. In low-sec, they also regularly face pirate groups such as Snuff Box, Shadow Cartel, etc. that have titans and capital ships and logistics doctrines of their own. Rather than being the 'big fish in a small pond,' they have other dedicated opponents who have made low-sec the end-game and fight with comparable numbers.
That few of these opponents make their home in the Caldari militia is not something you can blame them for.
Edit P.S. - Early last year, Pandemic Legion occupied Amamake.
SOTF organized and attacked a Pandemic Legion Titan, managing to destroy it while risking (and losing!) a fair number of their own dreads. Last Alliance Tournament, SLAPD went all in and made it to the final day, winning matches against some longstanding AT veterans and committing billions worth in ships and entrance fees in doing so. What kind of "bigger challenges" you'd like them to "dutifully" move on to?