Do keep in mind that if you've got a flood, fire, or something else happening to your pc, it will be lost. That's why I'd recommend an off-site backup, or at least to somewhere else in the house than where the pc is.

in the span of a single month is next to zero

It's much higher than zero, if let's say your ssd goes kaput & you try moving everything at once to a new one. That action by itself comes with risk, especially if the usb stick is very large & manufactured after covid. There is also the bit rot issue, usb sticks are useless as backup solutions for any use case, it's just a false sense of security.