You may find this interesting: https://www.t-nation.com/diet-fat-loss/research-approved-carb-cycling
It effectively talks about a study that suggests that a variation of a 5:2 strategy can have the same level of fat loss as a fully ketogenic diet.
I think ketosis is useful for therapeutic purposes, but I would really struggle to follow it in perpetuity. Personally, I prefer to structure eating strategies that I can follow for the rest of my life. So I'm never really 'on' or 'off' a diet, and am just always eating well. I think that 5:2 would be something easier to maintain long term.
My 2cents, feel free to discuss/disagree/continue the conversation!