This isn't exactly new territory. A lot of countries are very careful to avoid letting you in on a tourist visa if you give off the appearance of entering to work.
Because there is no visa process for short term professional work in the US, and never has been.
> A lot of countries are very careful to avoid letting you in on a tourist visa if you give off the appearance of entering to work.
That's just wrong. Virtually the entirety of the professional world travels around between industrial countries on tourist visas. Otherwise anyone going to a trade show is an "illegal" at risk of deportation.
And if you don't come from a preferred part of the world even the former can quickly be quite a process to prove it.
No thanks. I'll stream the conference online.