I rather wish that the Arduino API included a "self_reboot();" function.
It could do appropriate watchdog magic on older AVRs, and use the "reset controller" features that are present in newer AVRs (like the 4809 on the Uno WiFi2, and most ARMs.)
Having to continually tell people "to reboot, do this weird thing with the WDT (only be careful to also do X and Y) and infinite looping" is silly.
(alas, there is this ambiguity as to whether "reboot" means "run the bootloader to maybe get a new sketch" or "re-run the current sketch immediately." Watchdog use usually implies the latter. SW request maybe the former.)