Or try this:
$ sudo apt-get install libwayland-egl1-mesa-lts-xenial libwayland-egl1-mesa-lts-xenial:i386 xserver-xorg-lts-xenial xserver-xorg-core-lts-xenial
I don't get any conflicts from that, either w/o libsdl2 at all, or with it installed from your PPA.
Or try this:
$ sudo apt-get install libwayland- egl1-mesa- lts-xenial libwayland- egl1-mesa- lts-xenial: i386 xserver- xorg-lts- xenial xserver- xorg-core- lts-xenial
I don't get any conflicts from that, either w/o libsdl2 at all, or with it installed from your PPA.