It's close to sharepoint and sharepoint takes around 15MB to download.
If you want to run something like sharepoint suite locally, this is the best option. Question is - do you want/need to run sharepoint locally?
I hate javascript and I have it off by default. With that being said, this is a huge app with tons of options. Other apps without compression are just as bad
Draw io - 25MB
Outlook - 30MB
Gmail - 30MB
The difference is, this is oss, anyone can contribute and fix it