Clover is a hack to get a Hackintosh up and running by whatever means necessary, whereas opencore is a boot loader doing it's work exclusively in the environment as per the UEFI specification, leaving the underlying operating system, whichever that may be, for which it provides the necessary startup code, completely untouched. The way to go, at least as far as I am concerned.
For me there is no turning back to Clover, besides updates to kexts as well as new kexts, are not guaranteed by the opencore developers to continue working in a Clover environment, as they are not anymore tested for compatibility with Clover.
I assume sooner or later everyone would have to switch to opencore. To me the arrival of Big Sur seemed the right moment to do so because Clover can only boot macOS versions still using pre-linked kernels. The last macOS released by Apple with this particular technology has been Catalina. For mainly security reasons I guess, Apple has dropped this technology, from Big Sur altogether, therefore goodbye Clover, and welcome opencore.
Greetings Henties