I can do 25mph on my road bike on a flat road for 10 minutes, and i'm not that good of a cyclist. 25 mph is way too slow for city speed limits and nobody drive

I can do 25mph on my road bike on a flat road for 10 minutes, and i'm not that good of a cyclist. 25 mph is way too slow for city speed limits and nobody drives it as a result. The minimum standard should be 30mph. In Canada the standard city speed limit is 50km/h, which converts to about 31mph. I find in Canada that people tend to follow the 50km/h speed limit far more readily. Nobody really follows the 25mph limit in the USA. Since people like even numbers, the standard speed limit in america should be 30mph, not 25mph.