Why the facination with integrated amps?


I don’t get it. Is it the manufacturers spotting a trend with the tail wagging the dog or does a significant market segment truly prefer the idea of an integrated?
Pros;
Less space
One less set of IC’s
In theory-one less chassis/case to pay for
Shorter signal paths possible
Can combine transformer/cap function
Cons;
Power supply interference/spuriae
Reduced Flexibility-can’t switch amp or preamp as easily or go to monoblocs
Less resonance control
Long history of lesser performance per measurements and long-term subjective listening
Less resale value if it turns out to be a fad
Less liklihood of an extremely high performing active preamp

I freely admit I am a skeptic. The industry-like so many others-looks for new market niches to move product. 
FWIW, the only integrateds I myself would care to audition would be from Esoteric and Luxman who have a long history of designing no-compromise (low-compromise) high-end integrateds. 

128x128fsonicsmith
A separate amp and preamp has the flexibility that an integrated does not have!
I used to favor many "boxes" in my system then had a sea change toward simplicity and less boxes....now I use a tube integrated fed by a streamer DAC...I'm very satisfied.
OP we could not possibly disagree more. Oh well, it is the nature of these threads. Noise, noise, noise and noise again.  If you think short signal paths mean nothing, then I cannot help you. You asked why integrated gear is hot and you now need to be open minded about the reasons and possibilities. Carry on. 
Best sound I have ever had is with my Lyngdorf 2170 one box wonder.  I still build tube amps for fun, but the 2170 with room correction and built in dac simply sounds better.  I mentioned some of the reasons above and they do in fact play a role.  The times they are a changing and broad brushed statements bemoaning digital or Class D etc... are just plan old short sighted.  The innovation pace of all things digital and music is very fast,  very fast indeed. The fun and exciting part is all this is leading to more and more one or two box solutions that use little energy, are light in weight and sound phenomenal. 
For me it's bang-for-the-buck. I saved for 3 years to splurge on an Ayre AX-5. I'm not aware of separates at this price point that sound as good.