Comment 4 for bug 1942437

The first two wallpapers weigh 8.8MB. We're still waiting on the official wallpaper from the design team, but in the last few releases it weighed on average around 1MB.

For future reference, here is the list of total size in MB for each release's wallpapers package:

5,3M karmic
3,8M lucid
2,5M maverick
3,1M natty
2,4M oneiric
2,5M precise
3,4M quantal
2,3M raring
4,8M saucy
8,0M trusty
9,6M utopic
15M vivid
14M wily
17M xenial
12M yakkety
12M zesty
12M artful
36M bionic
19M cosmic
15M disco
7,0M eoan
12M focal
6,5M groovy
1,2M groovy-raspi
6,0M hirsute

Given the trend, I'd argue that keeping only the first two winners is reasonable.