Thanks for reply bor. You are right about everything & I also learned new things like the FUD myth which made mariadb popular. I guess if we start to compare who is the best, there will be no single winner; as each have their on pro & cons. Also it depends upon each user's unique requirements.Go with mysql 8 - it's backed by the giant Oracle. mariadb is a fork created by the original author of mysql. But they're a small entity, and will not be able to match the footprint of oracle.
A few years ago there was a FUD that Oracle may kill mysql, that's when mariadb gained popularity. But that turned out to be a myth, mysql is adequately supported (perhaps not as well as Oracle's main product, but nevertheless it's actively developed) At this juncture, there aren't many valid reasons to choose one over the other apart from big corp licensing restrictions. mariadb may be slightly more performant, but it's less reliable too. in most cases you won't notice a thing.
I personally use mariadb because it's a smaller download and you can just dump the portable version anywhere and get going.
After reading all replies, reply from PMs, c-panel support team & my hosting support team; Currently I have decided to go with mariadb in the new server & in next new server which I will buy in next 1-3 months, I will use MySQL 8. Then I will compare & learn what is really better for me.
Oooooh whatttttt...There is another database too..I thought the big ones are mysql and mariadb only.....haha so silly me..May be there are many more..Thanks to you I learned about pgsql.Personally, I prefer pgsql over mysql for my projects.
But No more overthinking or comparing. I will just test it in my new server & then compare. Hope it support wordpress & c-panel.