A Mac user,who invested some money in..let's say video editing software,will drop mac to play Swc poker? Think not.Same goes with android users,who are not always in front of PC.Will i take laptop at work?Never.Might even lose job.
Doesn't matter what new fancy games Swc has, if they are not accessible to all.
Most of the other 2/3 rds were most likely a mix of people who couldn't recover account (there were issues with emails), people who always had multiple accounts logged in the old site, which there were many, some who wouldn't have known about the new launch and probably even a small few who might not want to return on the new site with new owners.
There will be people on android that couldn't play. Most people with Android phone have a PC though.
I'm not saying they shouldn't have clients on other systems, far from it. Just saying that most users are Windows.
There's zero reason for the devs to waste time and money on a linux client. A web based client would do for the people playing on Linux and Mac.
Android client would be a good investment after web client.