Honestly, this isn't necessarily a bad thing for either Power Rangers OR Sentai. PR, should it continue in some form whether animated or live action, will no longer be beholden to to the already filmed footage. Which is a net positive for storytelling. And perhaps this means Shout Factory can get back in the business of releasing Sentai on DVD (come on Aba, Deka, Magi and Boukenger...).
It's too early to do anything but speculate on what this could mean for either franchise. Hell, in five years we might be looking back on some great PR and thinking how awesome it is that they freed themselves from Sentai's footage. Or maybe we'll all weep about Hasbro finally killed PR. Who knows?