Oh right, yeah, Wordpress does tend to use up an awful lot of storage - every image gets copied 5 or 6 times, in different sizes just incase you need that size. It's nuts.

You don't need to store those images in your server though, they can be uploaded to S3 (object storage) where it is 10x cheaper to store them and then you can have a cheaper VPS. This way the VPS only needs to have enough storage for your MySQL database.

https://wordpress.org/plugins/amazon-s3-and-cloudfront/

There are many providers of S3-compatible storage, you don't need to use AWS. Cloudflare R2 is super cheap - https://www.cloudflare.com/en-gb/developer-platform/products/r2/ or Hetzner - https://www.hetzner.com/storage/object-storage/