Il motivo è che le Ubuntu e derivate impostano il RTC in UTC.
Per risolvere basta digitare:
timedatectl set-local-rtc 1 --adjust-system-clock
se lanciate timedatectl vedrete un messaggio di warning e il modo di ritornare alle impostazioni originali:
Local time: dom 2023-02-19 10:14:02 CET
Universal time: dom 2023-02-19 09:14:02 UTC
RTC time: dom 2023-02-19 09:14:02
Time zone: Europe/Rome (CET, +0100)
System clock synchronized: yes
NTP service: active
RTC in local TZ: yes
Warning: The system is configured to read the RTC time in the local time zone.
This mode cannot be fully supported. It will create various problems
with time zone changes and daylight saving time adjustments. The RTC
time is never updated, it relies on external facilities to maintain it.
If at all possible, use RTC in UTC by calling
‘timedatectl set-local-rtc 0’.