as far as I can tell, the Follow-up function will work "always" since it has very low requirements (there should be just bpm-engine and api-web running - it is a simple process with a timer that assigns task to creator, so no further services are needed), so unless customer explicitly does not want to use it, or you do not want to use it due to licensing (cost), you may consider leaving it. It is a small and useful function that lots of our users like. It is also a first step for customer in direction to workflows, which increases acceptance of WFs and that is in the end good both for us and for customer - we get to build them and customer gets polisched processes to streamline daily work.
If you still would like to remove it, then "My Follow-ups" should be removed as well in the menu. Martin can tell more about it here.