Blizzard folks are working on bringing Diablo 2 closer to the modern eye candy standards but it seems like the game will miss the multiplayer ones that were present for decades.
Warcraft 3 Reforged was a disaster for many reasons but one of them was certainly the crippling changes to the way multiplayer worked and the removal of the original game along with the freedom it offered.
Hopefully, Blizzard learned some lessons from that horrendous release but given the lack of some multiplayer features in Diablo 2: Resurrected, it appears they are willing to repeat certain mistakes.
Namely, the game will be missing TCP/IP multiplayer as well as couch co-op . The latter is self-explanatory - even though Diablo 3 has such a feature, those who were hoping to play through D2 with a friend locally will not be able to do so.
Meanwhile, TCP/IP is a bit more technical but it's essentially a feature that allowed original Diablo 2 players to use Peer-to-Peer (P2P) connection and bypass Battle.net entirely when playing online. In local terms, it allowed players on two computers to play together via Local Area Network (LAN).
According to the official FAQ , this was done to avoid potential "security risks" but the community pretty much settled on the theory that Blizzard is simply removing these features to force engagement numbers up on their platform as well as combat piracy, at the paying players' expense.
Considering the stealthy way of announcing the lack of TCP/IP, which is obviously a step to avoid backlash from the fans, one does have to wonder about these supposed security risks.