Both OpenWRT and MikroTik are serious router platforms, but they optimise for different people.

OpenWRT

An open-source Linux distribution for routers. Huge hardware support, a package ecosystem, and full control. Its strength is flexibility and price — it runs on very cheap devices — but the raw experience is aimed at people comfortable with configuration.

MikroTik

A commercial platform (RouterOS) with powerful, consistent hardware and a deep feature set aimed at ISPs and network professionals. Very capable, but it is a closed ecosystem and its interface assumes you already know networking.

The practical choice

For a home, a hotel, or a café that wants filtering, a guest portal and parental controls without hiring a network engineer, OpenWRT is usually the better base — and a packaged plugin on top of it turns raw capability into something you can actually operate. Compare what each offers for guest WiFi before deciding.