No team I ever met was self-motivated to fill out bureaucracy tickets.
The question you should ask is: who wants them to count hours and why.
Then find out how to solve that need.
Ideally, you have a capacity for each team member and that capacity goes down when you have meetings. A person there for 8 hours per day might only have 6 hours of capacity. ...
The Scrum Guide states that:
Product Backlog items have the attributes of a description, order, estimate, and value.
Note that Scrum does not define the units for an estimate (Story Points, calendar hours, ideal hours, or something else). It also doesn't say that the estimate needs to be numerical. The purpose of the estimate on the Product Backlog Item ...
There are a lot of other bureaucratic processes here in place. [...] they have a bloody task called "Communication strategy" where they log hours for internal team discussion. I have been told it is because current PM wanted to track that.
There's your problem. Your Team is under the (apparently correct) impression that the culture of your workplace ...
I assumed here that by 'other essential activity', the OP meant administrative work/meetings similar to the Daily Scrum. The OP has clarified - leaving this Answer for posterity.
E.g. going from 8 hours per day to 6 hours per day, plus 2 hours for other essential activity.
Why do you have two hours of daily administrative work??
The Daily Scrum should ...
First we need to define 'Accuracy'.
If we overerestimated, then it's simple - if we spent 1/3 as much time, our accuracy was 1/3. 1/N x estimate = 1/N accuracy.
Underestimating, though, is the complicated part. What I'm going to assume is that if we spent 3x as much as we estimated, then our accuracy is 1/3. N x estimate = 1/N accuracy.
Assuming you want ...