If Roblox is able to address this issue, it would improve my experience using the forum because I would be able to remove my old comments on the devforum (which do not contribute to the community) easily.
This is limited to prevent abuse. Generally speaking, deleting posts in a forum setting is not appropriate because it impedes the ability to read discussions if posts are removed. We don’t have a way to tell “this post should be acceptable to delete or not” when you hit the delete button at the moment, so we have to be strict on the limit. Reducing the limit would have other, more undesirable effects.
Please avoid deleting posts that are a part of a discussion. All of your posts are marked with a date, so people can see that a particular comment was made years ago and may no longer be your current opinion. If you must delete old posts that you feel do not contribute to the discussion, feel free to do so over a longer period of time as the limit allows.