Bookmakers like Blackie will always be around and have an answer to bigger platforms
Offshore bookmakers will ALWAYS have an edge over these guys and a large one. As a private operation - an offshore book doesn’t not have to answer to anyone. No public shareholders, no foreign government regulator and the ability to take a short term loss to maintain their market share.
I’ve said it before and will repeat - these exchanges have a couple of vulnerabilities - mainly they are EXCHANGES- so when too much money comes in on one side the other side of the see-saw goes up (often too high) and creates opportunities for arbitrage players. Then there’s the lack of volume in many non major sports markets and even at times in major sports markets - panic selling creates problems. Finally - to combat these 2 issues - markets will likely have to seed the market with their own money and own market makers - and it doesn’t take long if they misjudge or get greedy with that appetite for risk until they are suddenly negative equity.
Places like Robinhood are riding a high right now - but markets change rapidly. Trying to be everything to everyone rarely works out long term. E-trade tried it a generation ago as the investing hub. These places are acting less and less like banks and more like .com startups circa 1996 every day and it’s a time bomb waiting to blow. As a bettor - you can’t ignore them right now - but just like any book - never keep free cash just sitting there - that’s what hard assets and real bank accounts are for.