Why is the Honda Civic so popular?

Everyday on the road, I see one specifically the 2016-2019 models that have the daytime running LED's and the cars front looks so aggressive.

But when I go inside there's like no space for back passengers but that is my only complain other than the 158 HP.

Because it ages well, like a Volvo, but cheaper.

The older models are known to last pretty long and gain high mileage without accumulating many mechanical issues

Where I live lot of people buy honda civic to modify the car and use for racing purposes
maybe that's the reason for its popularity here

You certainly are fascinated with the Civic. You keep asking the same question over and over.

They're reliable, I own one and have no issues with the space in the back. Unless you're looking at a coupe there's plenty of space back there.

Actual question being asked: "Why do people buy things I don't like?"

This, incidentally, is why no one should ever ask your advice on anything.