if it had been up to me, sports gambling should have been restricted to physical locations, and marketing prohibited or highly restricted (perhaps only print advertisements in local markets informing people where they can gamble). perhaps also allow an existing customer to place bets via a telephone call.
the way I think about it is, the main reason you want to legalize a vice is to prevent criminals from selling it.
so you want legal operators to have an easier time doing business than the criminals, so they can outcompete them -- but just barely.
app on your phone and unlimited marketing on the internet and primetime television goes way too far.