Playing on a small screen, is uncomfortable. No matter how you look at it.
All you're doing is trading in the convenience of a big screen for the convenience of gambling on the toilet at work. Personally to me, its not worth the trade-off.
Also, physical casinos are a completely different experience and they cannot be compared to online gambling. Not that you would know

I will agree with this, if other people prefer to gamble by using their smartphones then that is their decision and I respect it, but if given a choice I would pick my PC over my smartphone.
To begin with I do not have to force my eyesight when I play with my PC as I can easily increase the font of everything to whatever size I want without any limit, now my eyesight is still perfect but I know a lot of young people that have to use glasses already because of their smartphones, besides a mouse gives you way more precision than using your fingers so this reduces the chances of making any kind of mistake and misplace a bet or betting more than what you wanted on a single bet.