Reading the Reddit post the developer of the app wrote it seams like it's up to Samsung to bring this feature back.
An alternative way to bring up the band selection menu is to use the app Activity Launcher. At least up until the May 2022 update this worked. When searching for "hidden" in the App the first result for me is an activity called "com.samsung.android.app.telephonyui.hiddennetworksetting.MainActivity" which is part of the Call settings app (not the normal Call app).
With the May 2022 Update there are a total of 50 activities part of the Call settings app.
It would be interesting to know how many activities the Call settings app has with the June 2022 update and if this activity still exists (maybe under a different name).
Dam If I had known this I wouldn't have updated. This is last time I will update early. Bring the feature back Samsung or this will be the last Samsung phone i'll buy