Point remains, many events are linked to local civil time, which can change - and not just to daylight saving. The Line Islands in Kiribati shifted a whole day in 1994, same with Samoa in 2011. Have an event set for 0800 local on the first Monday of the year in Samoa which you stored as UTC, and your events would have broken. Unless you store the relevant data (it occurs on first monday according to the timezone that Samoa is in), then you will be wrong.

Now of course you can still get problems if a new timezone is created, as time is stored as Europe/London, if Scotland creates its own timezone in the future a meeting in Aberdeen would no longer be in Europe/London but in a new area Europe/Edinburgh, with different behaviour, but that’s far less common than DST changes or other date shifts.

All in all you should store the relevant datetime and zone, not just “normalise” it to UTC.