Using a modern sealant does no harm. It's a relatively quick extra step that simply offers more protection and even amped up shine. There's really no reason
not to do both. In general, people are traditionally familiar with the "wash and wax" philosophy. But any detailing writeup here written by a professional will include both sealant (longer term protection of 3-6 months) and an LSP (last step protection, 3-6 weeks) which is usually a carnauba.
Honestly, the sealant is even more important in terms of protection than the wax - especially on a daily driver. Some opt to save a step and not top the sealant with a wax, that's perfectly fine too. Sealants these days do provide a great shine. But for the best look possible, doing both is the way to go.
