We [customers of Apple] have no idea - and yes it worked perfectly before.
For reasons known only to Apple, the User Interface (UI) was substantially and inconstantly reworked during the transition from iOS 11 to iOS 12. It appears that the new gestures now implemented on the 2018 iPad Pro models, lacking the Home button, have also been applied to all models of iPad that have a physical Home button.
As a discussion point, what actually makes doubtful logic is that iOS gestures now lack a sense of consistency between devices with similar physical controls.
In my humble [and irrelevent] opinion, it would have made considerably more sense for Apple to retain the original/consistent UI shared between iPad and iPhone devices with a Home button - and implement the “new” UI for those new devices that, by design, now lack a Home button. This would have preserved consistency between devices that share a common set of controls. Alternatively,, Apple might have chosen to provide its customers with a configurable binary choice of UI - for those who choose to live with a mix of devices - but sadly, they didn’t do that either.
Alas, if you have strong feeling on the issue, you, personally, have a channel available to you to express your own opinion directly to Apple:
https://www.apple.com/feedback/ipad.html
Unfortunately, you are very unlikely to receive any comment or response in return for your input - but Apple do, reportedly, read all such input.
