FWIW we're not allowed to tip casino dealers in Australia
either, I'm pretty sure you can't in New Zealand
and I have a feeling the same is true most European countries as well? Here at least it's for exactly the reason that NoWucking mentions above: it's a huge game security issue, particularly at table games where there's huge potential for dealers to favour players who tip them well.
The article quoted above is laughable - when I think insane preflop action I think of live games, not vice versa. The only games I know where the standard opening raise preflop is 5BB or higher are live games, not online ones.
As for the original question I doubt there's been a huge surge. Most of the higher stakes and more successful online players already
play live so there's not likely to be much change there. Many of the lower stakes online grinders will have big chunks of their bankrolls tied up online at the moment so they probably won't have the funds available to skip straight to their local card room (if they even have one) and even those who do have access to their money may run into bankroll issues. Someone rolled for $50NL or $100NL online will have a hard time adapting to the swings of live games where $200NL is usually as low as stakes go.
I'm sure some of them will migrate to live poker in time but I don't really think there's going to be any kind of surge or mass influx.