Probably you were denied personal health insurance not for BS reasons, but because the insurance companies knew they would (probabilistically) lose money insuring you. But now under Obamacare, if they participate on the exchanges, they are obligated to sell to you. So, shockingly, we see that most companies operating on the exchanges lose money doing so.
Your inability to get coverage before and the problems that Aetna is having today are very closely related.