If you just want small file sizes but better quality:
If you download a pack labeled "Doraemon All Episode 3gp Videos" today, manage your expectations. You will not find Netflix quality. Here is the technical reality: Doraemon All Episode 3gp Videos
As of late 2023, AV1 and HEVC have replaced H.263. However, the 3gp format holds a UNESCO-worthy status in digital cultural history for anime fans. It represents a time when you had to wait 20 minutes to download a single episode of Doraemon via Bluetooth from a friend in the school bus. That memory is encoded in every grain of those pixels. If you just want small file sizes but better quality: