Please remember to keep discussion civil. No, this isn't the end of Warframe. The same sort of over-sensationalized prophesying happened 4+ years ago when Leyou (formerly Sumpo) bought shares in DE; people said it'd turn into 'all-lootboxes' and 'pay-to-win' and that DE 'would have zero control' and guess what? All bupkis.
Speculation is fine, as long as you're cognizant of the difference between opinions and facts, and as long as you're not spreading misinformation (intentionally or not). If you feel so strongly about this that want to leave the game, that's your prerogative (and loss) and is also fine.