Um, no, x86 CPUs are nothing like ARM and I'm not aware of any commercial x86 CPU with an ARM backend. Yes, modern x86 cores use a RISC-ish microcode backend with an x86 decoder frontend, but that doesn't say anything in favor of ARM. All it means is that the industry has collectively agreed that CISC as a microarchitecture is a stupid idea - not necessarily as an instruction set.
I'm not a fan of x86 myself, and I think it's a stupid design with a vast amount of baggage causing a significant power/performance impact when designing an x86 CPU (that Intel can get away with because they're a generation or two ahead of everyone else in silicon tech), but then again ARM isn't the pinnacle of RISC either (though I do think it's better than x86).
Me, I'll take whatever microarch gets the best performance per watt at whatever TDP is relevant. If Intel can pull that off with x86-64, by all means. If ARM AArch64 ends up ahead, awesome. If both are about equal, I'll take whatever's more practical based on other factors.