... I would also recommend the use of a $20 quiet infinity fan.
The reality is, not a lot of HT users have the kind of budget and knowledge that you have, so I don't think we should shy way from suggesting AVRs to a lot of users on a budget and may not have the real estates for more multiple boxes options.
I agree - and folks should look hard at the Fan option. It's cheap insurance. Heat is the most obvious killer of AVRs. I have them on the AVR in my Atmos system, even though I rarely drive it that hard.
Six Sigma training advises that the more opportunities for failure that exist, the less reliable a system is inherently. While it seems that separates would be more reliable, I suspect there are more components collectively inside all of these separates (for example each one has it's own power supply), more soldered connections to fail, air passageways to block, interconnect cables, etc., Of course the design and build quality of separates may give them an advantage, but typically they cost a lot more than the average (or most audiophile) consumers are willing to pay.
This is not to mention the increased complexity separates add, which causes folks to avoid them altogether. Even today's AVRs with Atmos and up to 13 speakers, are daunting for most folks. Even though they can sound great when properly set up, most consumers do not buy even AVRs with great abandon. The market for Home Theater and high end Audio has shrunk dramatically in the 2000s. The more complex it becomes, it scares off more people.
Just my 2 cents...
