My opinion that the development of services like this + overall market maturity = will lead to decreasing of spreads for arbitrage trading (as more and more people will be involved trying to catch higher spreads).
I believe the inter-exchange arbitrage market may have the most competition. So many people using bots to make 1% at any given time but the cross-exchange arbitrage opportunity you have an average of $50 million to $75 million from my research
https://medium.com/@chasarcaulon/arbitrage-alerts-for-cryptocurrency-spreads-in-real-time-c982c1f63a8b that are pumped into these coins in a matter of minutes which leaves room for thousands of people to profit from. It's smart to just risk a certain amount so I stick with 7k - 40k. It does not hurt me at all. I can only handle getting so many orders filled by myself therefore it's enough for me... so people trade with various amounts it's still enough opp for everyone it's a competition whoever can act the fastest pretty much. But I never lost on any. It's more of a casual thing for me. If I happen to get an alert when it happens and Im ready I'll do it.