I think there should be a choice. Pay less and replace avr (or anything else) every 2 or 3 years. Or pay more for more reliable brand and keep device longer. To me yamaha is that second brand offered without much premium. Though i would say there should be more brands like that.
So we have several options, such as the following:
1. Pay less and replace a last year model
*, entry to mid range avr every 2 to 3 or 3 to 5 years.(US$500-US$2200)
2. Pay even less for the same as in 1) but for a last year model, brand new with full warranty. (US$400-US$1800)
3. Same as in 2) but start with a lower mid range models, use as prepro set Eco mode* to "On".(US$600-US$1800)
4. Pay much more for a last year prepro. (US$2500 and up)
For some people 3) is better than 4) because then it is possible to simply get a 3 or 5 channel power amp while for others 4) is the best way because they believe (I don't, not any more) prepro offer better sound quality, more reliable* all else being equal. I went from 4 to 3 and am impressed with everything except reliability*, that remains unknown, but will find out in x years.
Either 3) or 4) will require a power amp, price range US$500 and up depending on power output and number of channels requirements.
*Last year = 2017, those models typically come with the latest features including Atmos, DTS:X Airplay2, eARC, 4K, HDR10, Dolby vision. Nothing is future proof, but in terms of future proof, buying the 2017 models seems safer than buying the 2015 models in 2016, and much safer than buying the 2012 models (the big gap between HDMI in 2013.
*Eco mode for the D&M models appears to have no effects on the dynamics, that's according to their customer support, and I tested it myself, at reference level. It does cool my AVR-X4400H down for several degrees C.
*Prepro reliability? - Seems like a reasonable assumption that they should be more reliable, but I would suggest before anyone investing $2500 to $4500 (e.g. Marantz),do a search using key words such as issues, repair etc., and one will see they do suffer from most of the same that avr users faced. Examples:
https://www.avsforum.com/forum/90-receivers-amps-processors/1535197-marantz-av8802-13-2-xlr-pre-pro-official-thread-491.html
https://www.avsforum.com/forum/90-receivers-amps-processors/2930176-marantz-av8805-15-2-xlr-pre-pro-official-thread-67.html
I would feel a lot worse having to send a $4,500 listed AV8805 to a repair center than if it is a $3000 SR8012.
The thing is, the internal amp sections don't really add that much chance of failure for most users, and one single quiet $10 Infinity fan will mitigate heat related concerns. We all know amps, if not abused, could last practically forever but prepros, and the prepro part of AVRs are much more prone to failure.
Prepro users do have the undeniable advantage that in all likelihood, they only have to replace their prepro, though in terms of overall probability of failure, it is quite complex if one factors in the two pieces vs one piece consideration.