Sorry for the delayed response. I've been very busy working on the release of 5.10.0, which has a lot of cool new features to check out.
In your situation, you are on a Pro account with 2 licensed users. This means each of your users can host a maximum of 1 meeting each, so overall 2 meetings concurrently for your account overall.
Unfortunately, Zoom does allow you to schedule more than you are allowed to host, without any warnings. Others have also expressed interest in such a such a limitation or warning, and while I cannot speak directly to why changes haven't been made, I've thought of a few reasons this may continue to be allowed:
Maybe you schedule a meeting and realize you have the wrong features enabled, so you quickly schedule a 2nd meeting and post the link in the first meeting. You have to end the 1st to start the 2nd, but at least you don't have to delete the 1st entirely before scheduling the 2nd.
Maybe your meeting has been Zoom-bombed or otherwise interrupted. You need to quickly schedule a replacement that hasn't been compromised. Once again, you don't have to end AND delete the first meeting to create a replacement.
Maybe you scheduled a meeting incorrectly, but never deleted it from your Zoom account. That accidental meeting might stop you from starting a meeting needed in that moment.
I certainly encourage you to visit our Zoom Feedback form, which is the official way to share any feedback or feature requests with the Zoom team.
Hope that helps and please make sure to mark the solution as accepted if this information is what you needed.