Public server DM defaults

The setting exists to disable DMs from all servers we join, however, many of us immediately think to small communities we are a part of or our main servers and decide to leave the setting on for convenience when joining future servers.

I recommend a setting, which is enabled by default, that automatically disables DMs in every publicly listed/10k+ member server unless you choose to enable it.

This is because, as a large server owner, I find that the number of bot raids that are comprised of thousands of bots go up significantly when your server is of that size, and it would be best if the majority of members did not have their DMs enabled for these scammers to spam by default.