SNES/Genesis/PS1etc have nothing to do with Switch/PS4/PS5. You're too focused on trying to force past historical patterns onto a situation where they are not relevant.
Looking at the past for patterns is the basis of all of science and really education in general. I mean, why even look at sales data? Everyone on this site who studies sales data is looking for patterns.
You are now trying to argue some weird solipstic world view where we can't know anything based on studying patterns, and science is an illusion. No one really believes this, even when they make this kind of argument. It's the type of argument a person makes when they stay to themselves, "I know in my gut you are wrong, but I just have no idea why."
Perhaps you need to examine your own thinking? Because you insist that a system (the Switch) either competes with both the PS4 and PS5 or competes with neither. Can you give an example like this? Do you think the XBox360 competed with both the PS2 and PS3 at the same time? Can you give any example of one system that competed with two generations at the same time? I can't. That is why a system, the Switch, which doesn't compete with the PS4 can still compete with the PS5.