As a general rule, yes. People who are able to better perform a task should be preferentially allocated towards those tasks. That being said, I think this should be a guiding rule, not a law upon which a society is built.
For one, there should be some accounting for personal preference. No one should be forced to do something by society just because they're adept at something. I think there is also space within the acceptable performance level of a society for initiatives to relax a meritocracy to some degree to help account for/make up for socioeconomic influences and historical/ongoing systemic discrimination. Meritocracy's also have to make sure they avoid the application of standardized evaluations at a young age completely determining an individual's future career prospects. Lastly, and I think this is one of common meritocracy retorhic's biggest flaws, a person's intrinsic value and overall value to society is not determined by their contributions to STEM fields and finance, which is where I think a lot of people who advocate for a more meritocracy-based society stand.