The tour question needs to fulfill a number of requirements:
- The question must be at most 400 characters long when rendered as HTML (not as markdown).
- The question can't contain any special formatting like lists, quotes, code, pictures, or headers. I think MathJax is ok.
- The question must have at least two tags.
- There must be at least two upvoted short answers without special formatting (same rules apply as for the question).
- At least one of these answers must have at least one comment.
- The question score must be at least 5.
I may have forgotten something; please edit or comment if something is wrong.
Questions fulfilling these criteria are eligible.
If there are no eligible questions, the tour example question will be a mock-up question about daisies and daffodils.
If there are several eligible questions, moderators can choose the one they want to show up by going to the tour page and clicking a button next to the example.
When a question turns into an example question for the tour, the scores shown are not real.
They are always the same numbers on all sites for the purpose of the tour.
Also the accepted answer need not be really accepted.
In your example the true accepted answer does not meet the formatting criteria.
Instead, two other answers were chosen.
I know this as a moderator on another site.
I agree that the example question could be chosen to be something else.
There is a great number of possible choices on this site.
Judging by this older meta question, the example used to be something else.
Perhaps the rules changed (disallowing MathJax in the title?) and that question was no longer eligible, and a new one was chosen automatically.
Or perhaps the question was changed but the new one subsequently became ineligible.
The fact that the question in question is the first hit on the list of eligible example questions ordered by ID (SEDE query) suggests that the current choice was made by a machine, not a person.
I don't know the full history, but it doesn't matter; what matters is choosing something better than the current one.
Could the local mods pick some question that looks reasonable?
We could then have a meta discussion to vote for the most suitable question for the tour?
[The question has been changed now.]