Crashing early is better than crashing later because it limits the damage and moderately frequent crashes creates some level of caution in the market. Propping up a market because it's too big to fail can in some cases create worse fallout. It's a judgement call though and I'm not entirely sure we have a really good rule of thumb here.
If there were a way to have enough transparency that we had smaller crashes more frequently it would probably help to limit the damage to those who can afford to lose it.
The truth is that you can only push a correction so far out. It will happen eventually and the farther out you push it the worse it will be.