Why does @Async work without @EnableAsync?

I'm using Spring Boot 2.3.5.RELEASE and I noticed that @Async methods in my application are working without adding @EnableAsync in any configuration class.

After some digging, I saw a comment from Marten Deinum suggesting that adding spring-boot-starter-actuator can enable @Async and scheduling by default.

Does spring-boot-starter-actuator implicitly enable async support?

When I add @EnableAsync and run, I get a BeanCreationException.

@Configuration
public class AsyncConfig implements WebMvcConfigurer {

@Bean(name = "taskExecutor")
public AsyncTaskExecutor taskExecutor() {
ThreadPoolTaskExecutor executor = new ThreadPoolTaskExecutor();
executor.setCorePoolSize(10);
executor.setMaxPoolSize(50);
executor.setQueueCapacity(500);
executor.setThreadNamePrefix("Async-");
executor.initialize();
return executor;
}

@Override
public void configureAsyncSupport(AsyncSupportConfigurer 
configurer) {
configurer.setTaskExecutor(taskExecutor());
}
}

@Service
public class TaskExecutorService {

@Async("taskExecutor")
public void sendEmailAndNotification(Candidate candidate) {
    // Your logic to send email and notification
}
}

this code work without error, but if I add @EnableAsync I get this,

Error