I get you OP, just back from Italy with the family, DC 2,5&7.
Beautiful lakeside location, zero safety measures at the hotel, lots of rocks in ice cold water, also an outdoor fucking freezing pool, completely open with no safety features, like a fence
Coping strategies: 1 adult on duty whilst the other chatted to extended family.
Strict boundaries regarding the area that the kids could play in i.e away from the waters edge.
Eat out at lunch only, self cater for dinner at a reasonable time.
One adult stays in whilst the other goes out for dinner with the family.
We had low expectations, never spent more than 2 hours on any one activity, and had filled the iPad with downloads from CBeebies.
Kids had great fun, but it was hard work. We set lots of boundaries, seemed to have a constant stream of 'no, don't go past that wall, no, don't go near the water' etc
And yes we need a holiday to recover!
It will get easier. Probably.......