In this case I don't think this would be on topic. It's a good question to ask, but it would spawn a discussion. It's one of those situations where the only canonical answer would be "it depends on..", the canonical part being the important bit.
At Stack Exchange, we're not a discussion forum, but more of a wiki. People post questions, and an answer is picked that represents the canonical answer for all people who have that question.
It's less about this specific instance of what helped you the most, and more like Wikipedia. So when you mark an answer as correct, you're saying this isn't just an answer that works, this is THE answer, objectively and factually.
It might be that an answer is the closest to that, or that after accepting, a new answer appears that debunks it with a deeper truth, or the same truth but written clearer and in more depth. That's why you can change the accepted answer.
But, for this situation, I don't think there is an objective answer that's true for all occasions. Without some limitations of context and use to frame an answer around, there's a certain level of preference. Sometimes you really want an event to be a term in a taxonomy. Sometimes you want to list the events and be able to comment on them and so a post is better. There really isn't enough information or context to give anything other than opinions.
It may well be that providing more context and information though, that it could be brought into the realm of on-topic, by making it definitively answerable in concrete terms, but that's not a guarantee and isn't always possible.
As such I can offer general platititudes and advice:
- If you need archives to list it, use a post type ( otherwise you'll need a page template, don't rely on page templates for your archives/listings, use archives for your archives )
- If you need to filter a post by the associated event, don't store the event in post meta, store it as a term, there are major performance difference between the two
- Terms can have meta too, and you can use the term archive to show some of this data at the top on the first page of the archive. It's not as convenient as a post, but it is possible, and may suffice for your needs
- ACF is offtopic, it's a 3rd party plugin. If a question requires ACF knowledge to answer or be understood, then it needs to be asked in an ACF community or ACF support