While I don't have a solution for the old controls, I do genuinely prefer the old action menu, as someone who's played a lot of Arma it just clicked immediately to me, while some of the keybinds were odd, the old system still feels significantly better to me. 
I really hope that in future it will default to the new system but gives players a chance to continue using the older system too.

Thats the neat part you cant.The Checkbox is bugged(Or you can if you know your way around game development and messing with game configuration files) 
Wait for an update on the shadow build(If DrNose doesnt get fed up with the community endless nagging and give a big middle finger to everyone by only releasing the fix  on the Stable 0.9.0. which is not that far) 
By the way the new control scheme is more accessible to someone with finger issues. And much more ergonomic and intuitive and its Also controller friendly which seems to be hinting at a VoTV release on consoles.
also no more grab/take/eat confusion YAY.

mod it i guess?  From what i see, the devs are persistent on the tap\hold controls, so we're better off letting modders be modders and fix it for us, OOOR we beg drmrnose to add a legacy controls mode. I'd favor either,  but it seems better if the dev did it himself for future versions.