This is one of the best things about PC gaming. I already have played two other "revived" games from my childhood extensivley in the past - NFS World and Battlefield Heroes.
Last time I checked ARM v7 is not the issue, there are still up to date builds available from Chrome itsself or Brave, rather Android 6 is. Google seems to have a cycle where roughly every fall they drop another Android version.
Right now the minium requirement is Anroid 8 and if the cycle continues it will loose support in a few months and Android 9 will be the new minimum requirement.
However I also have a a few Android 6 or 7 devices and usually firefox runs fine on them if they at least have two proper large CPU cores. But using two year old Chromium based browsers, I never ran into any sites that wouldn't work correctly.
Black Ops 2 had a pretty simple solution. A playlist where half the players on each team are pretty weak bots. I played this mode more than the regular 6v6 MP because it didn't force everyone to use the same 4 meta guns to do well.
God I love the web platform!