I disagree as strongly as possible with the statement I quoted/underlined here.
On default Discourse settings, I uploaded one jpg image which was 399.62 kB. Discourse decided that it needed ALL of the following “optimized” versions too:
| Resolution | File Size |
|---|---|
| 1014x748 | 307.84 kB |
| 1024x757 | 311.81 kB |
| 1352x998 | 470.51 kB |
| 200x147 | 16.93 kB |
| 300x221 | 35.19 kB |
| 400x295 | 59.38 kB |
| 600x443 | 125.43 kB |
| 676x499 | 157.57 kB |
| 800x591 | 207.09 kB |
This is an additional 1691.75 kB of storage on top of the original 399.62 kB. So from 400 kB to nearly 2100 kB, for a total of over 5x the size of the original size. One of the “optimized” files is even larger than the original too, which is hardly fitting of the term.