The default is still “admin” in the sense that it can sudo or equivalent. But quite a lot of the OS itself has been isolated from sudo/etc, and in recent versio

The default is still “admin” in the sense that it can sudo or equivalent. But quite a lot of the OS itself has been isolated from sudo/etc, and in recent versions isolated to a read-only FS. And quite a lot of the native APIs (eg file system access outside the app’s isolated storage) have been restricted to require asking for explicit permission before they can be used. Some functionality has even been restricted to require direct authentication (notably: password autofill in Safari). The FS access limitations feel most frictionful, but nowhere near so much as earlier Windows forays into this kind of UI; the downside of that is that it’s easy to forget what access you’ve granted. Most of the rest of macOS defenses depend on almost totally invisible malware mitigations. “Almost totally” as in you don’t even know it’s running unless you happen to spot it in a process monitor. Apple mostly strikes a good balance in macOS (IMO) between locking as many doors as it can without getting in your way, good default UI tradeoffs, mostly reasonable escape hatches if you really do know what you’re doing, and very inconvenient escape hatches for actions which truly leave your proverbial front door unlocked. (The latter involve rebooting into the recovery volume and entering explicit commands into a CLI.) If you’re a high value target, obviously none of this is sufficient. If you’re a rando user with relatively not-reckless habits, at this point it’s like gambling with odds so close to break-even most users have good reason to think it’s a solved problem.