Unfortunately, iPadOS15 has fundamentally and detrimentally altered the manner in which the Safari sidebar - and by extension the Reading List, Bookmarks/Favourites and History - are accessed and managed. As you observe, something that previously required a single touch, is now more convoluted and at best requires multiple touches and actions to accomplish the same action.
There is no workaround or method by which the previous behaviour can be re-established.
Apple do invite constructive feedback, comments and feature requests via their product feedback page. For iPad and iPadOS:
Feedback - iPad - Apple
You are encouraged to make use of this facility in expressing any views concerning issues, bugs, or functionality changes of which you are unhappy.