I agree with you, but at the same time I don't. Not having health indicators are what makes pvp fun in my opinion. With health indicators, people would just target the weak. Also, there would be so much running away if there were health indicators.
For example:
If there were health indicators, and I saw that I had 2 hearts and you had still half your hearts, I would run away.
But without health indicators, people would stay in the 1v1 and there is a higher chance of them not running.
And I'm not sure if it's just me, but I hate when people run.