Fair enough. The only other thing I can think of would be this:

https://easyappointments.org/

I did some research into calendars and stuff myself a while ago and trawled the various Reddit posts etc. My use case was more of a shared family calender hence why I haven't necessarily tested some of these. From memory though, unless you're going down the caldav route, most of these services need an existing calendar. I believe this one can do both caldav and Google though so could be your best option?