I am getting too large .obb file....

Whenever I package the project for android I get a way to large .obb file. my .apk file is like 45mb and .obb file is 436mb however my content folder size is 80 mb. Why is this happening?
I havent included starter content or anything else.
Total folder size of project is 90 mb. but still 436mb .obb file… i dont get it.
i am also using default settings of project to package.

Make sure to do all the tips here:
Also make sure to only use one texture type. I recommend ETC2 if you’re wanting to include older devices.