50 years ago when I was a little pup, half of the cost of an audio system went into the amplification stage (transistor or tube amplifier). Also, the main sound sources (radio, records) were VERY large (we had a roof antenna in our attic that was 10’ long!)
Today a good amplifier on an IC with decent power transistors can cost $3 and fits on a 2" x 2" circuit board! So under these circumstances, where the power amplifier is basically free & tiny, a speaker is more flexible if it has its own amplifier. Meanwhile the sources are mobile devices like smartphones which don’t produce enough power to driver speakers adequately. Or the sources are things all over the house (remote TVs, computers, virtual assistants) where requiring an outboard amp would be a terrific hassle!
Under these circumstances, shifting the power amplifier from the source to the speaker makes perfect sense!
Ever since 1995 I have felt it was wonderful to be able to buy a $40 AM/FM SONY Walkman + $80 high-end computer speakers and have a $120 home stereo that beats anything less than $450 at the time. The ability to make such mongrel systems is the greatest thing about self-contained audio where only the signal (and not the power) is passed between devices ...