I wish I could find a nice explainer on this. I heard this too, but not sure why.
If I understood correctly: Xen is a more secure design and has had a lot of work put into it (e.g. why Qubes uses Xen vs KVM), but KVM is: faster, in the kernel, and getting a lot more attention generally so in the future anything it's worse at now could get better because of the investment it is getting.
All the above is literally me guessing which is why I'd love someone to actually write a proper explanation as to why "KVM >>> Xen"
If I understood correctly: Xen is a more secure design and has had a lot of work put into it (e.g. why Qubes uses Xen vs KVM), but KVM is: faster, in the kernel, and getting a lot more attention generally so in the future anything it's worse at now could get better because of the investment it is getting.
All the above is literally me guessing which is why I'd love someone to actually write a proper explanation as to why "KVM >>> Xen"