Not if they pull some BS excuse like safety. Look at PS3 and other OS. Plus say 30000 xbox one's sold. They loose 50% in lawsuit. it's still 50% more than they would have before. I mean Microsoft didn't care that the 360 has the BIGGEST fail rate of any console why would they start caring about customers now?
Well, for one, if its a class action lawsuit they'd be responsible for paying back a large portion of those profits. It'd be an almost impossible case to lose for the consumers. Secondly, it'd severely hurt Microsoft's stock price and they'd be hearing it from their stockholders, which they do care about. Look how much it dipped just from the unfavorable Xbox One announcement. If they pulled another reversal, that stock drop would be far more. Third, it'd also destroy a large portion of their future online sales through their Xbox Live Service, since their consumer confidence would be in tatters, again even moreso after the intial Xbox One announcement. After the reversal to not require 24 hour check ins/online connection and restrictions on used games, their consumer confidence is slowly creeping back up, their stock is now up, and Xbox pre orders will probably increase.
As for them pulling a "safety" excuse, they can release software updates and patches without requiring 24 hour check ins or permanent online connections or restrictions on used games. Its comparable to releasing a video game for a console NOT requiring an online connection, then somewhere down the line converting it into an MMO requiring that connection and for you to log in and play every 24 hours to keep your account working. You bought the game originally with the expressed idea it ISN'T an MMO, and could play it offline. To change that is completely unfair to your customers on a level opening that company up to lawsuits.
Microsoft screwed up with the original approach to Xbox One, the fans reacted harshly and made it clear they (for the most part) weren't onboard, so Microsoft had to change their approach to regain some of that expected lost profit. The bad publicity, the lower than expected pre orders (the PS4 is vastly outselling the Xbox One for a reason, and that reason was the original restrictions), and the likely and expected slew of lawsuits Microsoft would face should prevent any drastic changes back to the original approach.