is it true that the MT feature become more diversitile if we install openWRT firmware on it..?
I did my first hotspot systems on mikrotiks, many years ago. Later on, I switched to openwrt for this purpose, because much more open, with many more packages to choose from, giving the opportunity of some specialities, i.e. example running a squid proxy, nginx server or coova-chilli CP on mikrotiks, some of which are officially supported by openwrt.
However, because openwrt is truly open source, it relies on the motivation of the developers, to adapt openwrt to new hardware (versions).
So, in case you "only" want a good and simple router, no need to use openwrt on MT. But in the area of IoT, for example, connecting a mikrotik to AWS-IoT, besides some routing tasks, is a good job for openwrt.
Last, not least, for somebody being familar with LINUX, openwrt is much easier to understand. And to configure.
In Summary: A hymn to openwrt software. And mikrotik hardware.