Well NiceHash attacks could well (should, even?) increase. It might not be too pretty, either - especially as it's POW coins that will take the brunt of it.
OK, I was wondering how shitcoins might be pruned, as is in a Darwinian way it seems sort of inevitable when there are obviously way too many with no real use case, or any likely long-term value. But the minimal money to wreck some fairly big name coins, rattles me a tad. It will not exactly be good news if it is widely received that POW itself is not safe.
I know BTC is a way bigger deal to attack and almost impossible, but...
I wonder if there's anything in Nicehash's terms about using their equipment for nefarious ends.
If you go after BTC you're going to get a ton of idle mining thrown at you rather like the end of Ready Player One plus killing a shitcoin means nothing. Attacking the foundation of it all would be very suicidal/ballsy.
In all honesty, I hope I am over-reacting. NiceHash can't rent you enough for 51% on most coins (and certainly not BTC) and an hour wouldn't work, i would need to be sutained. So it could just be the smaller shitcoins unable to respond (and lacking nodes) that are vulnerable... Bigger coins can presumably rent or mobilse fan-hash to defend themselves, or adapt POW algos, too.
But big coins need to not fail - you can imagine the media scrum and the wailing and gnashing of teeth on the wires of the scammed.