Google has been pushing Chrome as the default browser to use for some time. Everyone quits supporting obsolete software when newer/better one is available. Installing Chrome takes a mere minute and is completely free; no reason to fuss about it. If you prefer to avoid Google's browsers, go for Firefox or any other browser available on Play.
Anyone remembers IE 6.0? How long it took for that piece of junk to die? And how many systems kept using it, despite the availability of better browsers, just because it kept getting some support from MS? It's better to cut the losses in one move, IMO.
Google have a duty of care to provide fixes or force manufacturers / mobile copanies to provide updated roms for a minium of 5 years, if the next gen O/S is compatible with the handset, as most are with JB and KK..