It will be a disaster if a new Switch isn't available before 2025. Hardware wise it's already a relic.
Again, I'd ask a disaster in what context?
It's not selling quite as well as they perhaps expected and definitely on the decline but it's still comfortably bringing in huge sales numbers (pretty much competing with PS5 and XS combined for 2022 numbers) - we might not like it as gamers craving something new but we're hardly looking at a situation where Nintendo are staring down the barrel of irrelevance and ruin if they don't get something to market ASAP.