It's funny how these LCCs start as spin offs of what are perceived to be legacy carriers with their unnecessarily expensive seats and cabin class costs. They purchase planes that are new for the efficiency and make it a single class for the density. They add on some packages to drive extra revenue per pax like the bundles and then surprise surprise, back come the classes, but they're still nickel and dimed coughpy versions of the legacy carrier products (Scoot's new Scootplus generous 30MB wifi allowance anyone?) and by the end of it you've got what is a slighly cheaper but vastly inferior version of the legacy carrier's products that present nothing more than a veneer of cheap flight tickets to suck in unwitting buyers, upsell them with well marketed cough (bet Jetstar's $8 pot noodles are fantastic) and then cancel their flights and leave them stranded when they can't flog enough tickets.
LCCs are a scourge - change my mind?
Sorry, went 90 degrees off topic there. The answer is no, don't lower the value of mainline FF points with inferior jetstar alternatives. We already have to put up with this where JQ segments get sold into itineraries, which then bring down the cost of the full service carrier itineraries and end up cannibalisng business travel due to cheapest fare criteria leaving business travelers stranded or delayed, as little tie in as possible would be nice so they can ultimately be killed off and the routes reintroduced into mainline when people refuse to give them business.