> the android user will not see a heart on the message, and instead will get a separate text that says "Jimmy loved a message" and they can't tell which message you're talking about
The substitute message for the reaction (known as a "Tapback" in iMessage) does let the recipient tell which message is being reacted to, though it's not very user-friendly. The format is something like:
The Google Messages app,[1] which is preloaded on many Android phones, now automatically interprets substitute messages for iMessage Tapbacks and displays them as reactions, the same way iMessage users would see them.[2] Hopefully, this feature makes its way to open source texting apps soon.
Thanks, I could have sworn that before I switched back to iOS, I was getting a bunch of "<X> loved a message" from iOS users. Maybe it improved in newer iterations.