A few things here.
The databases for D2 are Regional only. They only have to handle the data for a single region. For a game that is 20 years old. There is no global play or console play in D2.
D2R is Global - as in all the data for all the regions and consoles all feeds into the one large database. While ok for an individual Region, it is not ok for Global.
They also have a timer on game creation in D2 (2000). And it gives you realm down or temp suspends you from the game.
Here are the server stability and anti bot measures in place right now for D2 (2000) . This tells me they KNEW these things were issues even at the Regional level. Much less the Global.
The Diablo II (2000) servers will automatically restrict connections when a game client is performing unauthorized behaviors. These restrictions exist to maintain server stability and prevent exploitative behavior such as botting and hacking.
If you are using an IP address which is shared with other users, any restriction will affect all users of the IP address. If you share your IP address with other players who have gotten a restriction, you will need to acquire a different IP address.
Connection restrictions in Diablo II (2000) can be applied for behaviors such as:
- Attempting to use an invalid CD-key
- Attempting to use a hacked or modified game client to log in to Battle.net
- Using unauthorized third-party programs or addons
- Connecting to Battle.net using a business network, cloud hosting service, VPN, or proxy
- Rapidly connecting and disconnecting from Battle.net
- Switching between accounts or characters too quickly
- Leaving and joining games too quickly
- Scrolling through skill selection too quickly using the mouse wheel
- Repeatedly leaving an area and coming back to change shop or gambling items
- Repeatedly using a spell with no cast delay such as Amplify Damage or Glacial Spike
- Repeatedly using an incorrect password
- Harassing other players
- Advertising inappropriate website urls
- Spamming text or chat commands such as /whisper or /whois
- Connecting to Battle.net with more than 8 clients
Repeated login attempts after a restriction may extend the restriction.
What they failed to do was FIX the issues that already existed THEN they applied it at the Global level across all the PC regions and platforms.
No surprise it keeled over.