You know, Garmin could really get dirty and get in the business of bribing Jeppesen (seeing as how bribery at the corporate level is actually legal in the USA... free speech says the SCOTUS... w-a-joke) to get them to discontinue database support on the legacy boxes. Thence forces the know-no-better captive audience we call the peanut gallery of this hobby to BOHICA onto the GTN touch doo da or whatever it is they spend the HELOC money they're about to lose in 2019 on. Like fish in a barrel. The Garmin sycophants of course would be none the wiser. They'd just get in line at the avionics shop and rationalize it as being money ahead somehow.
The used market has shown a great deal of resiliency in keeping orphaned hardware going. Really, it is a straight up compliment to us W-2 schmucks who keep trying to stay in this hobby by the skin of our pencil whipping teeth, flying these cannibalized 40-60+ year old AD-laden contraptions, behind 286 chipset GX-boxes et al. Fact remains, Ad hoc support of the antiquey variety has never been our limfac; the database is. The same will be true of the 480 boxes and KLNs alike.
The garmin 4xx(w) still enjoys enough market share to keep Garmin at bay, so a bribe attempt for that particular box wouldn't be feasible in present circumstances.
Condolences to those who just got their /G capability effectively ripped out of their panel. Seriously, I don't know what I'd do, especially in the eve of the ADSB mandate. Too many insults in a row for my taste. I'd probably sell, or just go tablet pirate. With friends like these....