Because we want to incentivize making each stream higher quality, rather than creating a bunch of one-off streams that don't actually have any content. We also want to avoid having people just reserve of bunch of stream names.
That would be a good rule. Only 1/100th of 1% of users would ever need that many. Since that would be the top users such as yourself who generate a lot of content (and therefore clicks) for imgflip, it would be beneficial. 👍