Part of the goal of 87 was that it should work for arbitrarily large groups, the bottleneck is the key sharing mechanism, but if you're an admin of a large group you can delegate that to a server. The main problem with it is also its main benefit, 1059's are completely opaque, and if you're a member of groups with lots of activity you have to decrypt a ton of messages before you can filter them.
NIP-87 has not been merged yet, but you can check it out here: https://github.com/nostr-protocol/nips/pull/875
imo, which NIP to adopt depends on what the client wants to achieve. My goal is to replace Telegram for large group chats, meaning supporting tens of thousands or even hundreds of thousands of members. Currently, NIP-29 seems to be the only one capable of achieving this. NIP-87, based on a shared key scheme, can protect privacy, but I think it limits group size to around a thousand members. Correct me if there are any misunderstandings nostr:npub1jlrs53pkdfjnts29kveljul2sm0actt6n8dxrrzqcersttvcuv3qdjynqn