$400 worth of Switch games, easy.
Most consoles simply don't launch with many games I care about. It would be a simple enough thing to wait a year or two for the software to catch up. This is assuming I'll want a PS5... for all I know, they'll botch it hard and I won't bother getting one at all.
Meanwhile, by the time the PS5 does hit, the Switch will have had a couple years to continue building its library. $400 is what, around 8 games at msrp? I'm sure I'll find 8 games I want.