Its always a bad decision to buy high whatever the currency and personally i didnt do this so far
Always when the bitcoin price is low the treu believers of bitcoin expect a recover and many of them always bought bitcoin at low price.
That's bad for small players who want to trade in bitcoin and most people maybe prefer to trade in another altcoin instead of bitcoin, but for the true hodlers it does not matter they will buy it as they can even in high prices situation.
It's the small players who end up losing their investment just like it happened last time since the fluctuations doesn't really matter for long term investors but small players make mistake of panic selling because thier situation and let's not forget those who have already invested during the last ATH are still waiting for price to cross last ATH.