Web apps can just up and disappear, spontaneously grow paywalls, or slowly enshittify over time, and unless both the user is technically savvy and the web app is fully open source, there’s nothing the user can do about it.
In contrast, when a new release of a native app is worse or its company goes under, the user retains a useful product (old binary) that can be run bordeline indefinitely one way or another (hacks, emulation, etc).