Does Anyone Here NOT Multi-Table?

one screen

I also like to play only one table, but for profitability I think I have to play more than one screen

Of course, if you are not a professional regular player - no point to play more than one or maybe 2 tables. If i play a freeroll and i,m going good, but soon starts another one with great money prize pool i can play a few tables, but not many of course.
If people play high limits also pointless to play more than 1 table. You need to watch all the game play at the table.

I prefer to play two to four tables of higher stakes. Multi-tabling is not necessarily a good thing. Typically the more tables you play, the lower your ROI per table. That isn't really disputable either -guys like Nanonoko will even attest to that. However, if you are being offered a rakeback program that is incentivized correctly playing 16-24 tables at "break even" can be very profitable. We used to see that on pokerstars. You won't find rakeback programs like that anymore. Hopefully when the US poker market changes we will also see a shift in the way rakeback is provided to players, at least initially.