I don’t think there’s any technical reason they couldn’t - often on military ships around helipads the barriers around it are netted and fold down when it’s ope

I don’t think there’s any technical reason they couldn’t - often on military ships around helipads the barriers around it are netted and fold down when it’s operational so you don’t fall off. Bit cruise ships are huge. For fall nets to be really effective, you’d probably have to have one under every level you could fall from. Some of these things are dozens of storeys tall - if you just had one around the bottom, it would have to stick out and be absolutely massive. Either way, the cost would be phenomenal. If they really wanted to make it completely safe they’d just make the balustrades taller than average head height and with no gaps a person could fit through, or put mesh screening all around or glass or something. But that would probably be ugly and would diminish the view people are paying for. So they’ve made the trade off.