Anyone on H1B who is working in US or is arriving into US for work will have to pay. F1 on OPT is F1 Visa and not on H1B. If they choose to get a H1B at the same time, if they use it to work then they have to pay.
I guess you didnt read the proclamation... 100k payment is only enforced at entry. F1 students when they are ready to apply for h1b are already inside the US
The 100K fee has to accompany the H1B petition. The enforcement happens at the port of entry. So theoretically, a) the application could be denied if it doesnt have the 100K fee. b) If it doesnt get denied then you could stay in the country without paying 100K till a change of status event? This removes any out of US travel options. Not sure how practical option b is, where you put everything on the line if a travel need arises.
