Before high speed internet was a "thing" you had to be on the LAN to get optimal multiplayer. Personally for my LAN culture died off when pings fell below 100ms over the internet instead of the 500-1000ms over 56K
You are seriously exaggerating ping times on old dialup connections. I played a lot of Quake in the late 90s and even on my 28.8 modem I could get 200-350ms pings to most servers and 300-500ms to distant servers. I never had 56k because although my ISP offered it, my phone lines then couldn't support it. Also, 200-350 was actually very playable because most other players had similar pings at the time, unless you went to an LPB server. But online multiplayer did thrive even before everyone had a high speed connection.