Tanking and what's the issue with them?

I've only been on WoW for about a monthnow focusing on leveling my main character which is a brewmaster monk and I chose her race to be a goblin.
I've been following this reddit for awhile and it seems like a lot of people aren't a fan of them and I'm really not sure as to why.

Should I cut my losses with this character and do something different? Or do you have any tips on doing the job properly?

At one point I was thinking of making an alliance character so I can unlock the iron dwarf and building a death knight.