During his personal Twitch stream, streamer, analyst, and professional player Andrey "Afoninje" Afonin explained why triple lanes have fallen out of favour in Dota 2.
He noted that the primary reason is that players figured out how to effectively pressure off-laners, even with just two heroes. Additionally, map changes played a role—previously, off-laners could move through trees more easily.
Afonin acknowledged that many factors contributed to the decline of triple lanes, though he couldn't recall them all. He highlighted a past meta where players could pull creeps from the first minute, which would have kept triple lanes viable today. Back then, off-laners could stack creep waves or lead them away. However, since this is only possible from the fifth minute onwards now, new strategies had to be developed.
Previously, Afonin had also speculated during a stream on which players could be considered among the best mid-laners in Dota 2 history.