You know that they intentionally put through and hyped up the worst singers, right? Like some kid who showed up for the first round on a lark was told "congrats you're great!! You're coming back for the next round when the judges are here," did the whole profiling/backstory thing like they'd do if you were a good singer, and intentionally set you up to fail in the worst way. Just so Simon can make a joke at your expense.
Whether or not the singers were hyped up for entertainment doesn't change the fact that they seriously auditioned, unless you think they tried out ironically for the lulz.
In the first case, rudeness can be helpful and in the second case it won't hurt their feelings. Seems like a fine choice to me.
