regression: can't set default calendar with created events

Steps to reproduce

1. go to calendar
2. go to settings
3. set "default calendar for incoming invitations" to a non-personal calendar
4. create a new event, observe the calendar the event defaulted to

Expected behavior

I expect the new event to be in the calendar set in the "default calendar" configuration

Actual behavior

is in the personal calendar

Calendar app version

6.4.2

CalDAV-clients used

N/A

Browser

firefox 139.0.4

Client operating system

gentoo

Server operating system

No response

Web server

None

Database engine version

None

PHP engine version

None

Nextcloud version

No response

Updated from an older installed version or fresh install

None

List of activated apps

Nextcloud configuration

Web server error log

Log file

Browser log

Additional info

this might be a regression of https://github.com/nextcloud/calendar/pull/5790 & the original ask: https://github.com/nextcloud/calendar/issues/1835, seems to be specifically reverted in https://github.com/nextcloud/calendar/commit/4f2caf615b8ecdcb0f2f63abd71093581a0a68bb

Reproduce the behavior in Calendar 6.4.2 by setting a non-personal default calendar and creating an event. Compare the current behavior with pull request 5790, issue 1835, and commit 4f2caf615b8ecdcb0f2f63abd71093581a0a68bb; done means new events use the configured default calendar.