You cite absolutely no sources, talk about a "site" this info is from and make claims with absolutely no evidence whatsoever. Are you even using Android? Are you using a $50 android phone running Froyo and using that as a reference for the software experience that everyone should be using to determine the quality of Android Lollipop, Marshmallow and Nougat?
Engadget gave Lollipop 9/10.
https://www.engadget.com/2014/11/14/android-lollipop-review/
The Verge also praised it. 8.7/10
http://www.theverge.com/2014/11/12/7203161/android-5-0-lollipop-review
Marshmallow reviews:
The Verge 8.5/10 -
http://www.theverge.com/2015/10/15/9542307/android-marshmallow-review
TrustedReviews 9/10
http://www.trustedreviews.com/android-marshmallow-review
Every review I have read for these new versions of the OS have praised Google's repeated success at iterating and evolving the Android platform to be more aesthetically pleasing while also being more functional at the same time.
On top of that who are you to evaluate the quality of a product you barely use regularly (15% battery usage in a day)? You didn't even bother the mention the device you are using and what issues you were having.
I see why so many people I know use iphones, I thought it was a status thing, but after playing with some, I realized it's because they just plain WORK.
Oh wait. I think I know.
It's a given that broadening the feature set will in turn result in higher system requirements but you can't improve software by thinking about how 3+ year old hardware will handle it. Most people upgrade their phones at least every two years so it would not make sense from an efficiency stand point to use the resources to indirectly support devices that barely anyone uses anymore.
Furthermore, Google does all of this while managing to sustain millions of different devices with different hardware configurations with Google Play Services that are able to run on a variety of versions (most support KitKat and up). If a two year old Samsung device can't run the latest version well the blame can't be diverted to Google or the OS.
As a user above demonstrated with an image most existing Android devices are running Lollipop. This comes from the Android developers site which provides this information so that developers know what versions of Android their apps should be targeting.
Additionally, I have witnessed first hand how these OS's are like on launch. I've had a Nexus 5 running Lollipop and it was excellent. After that it got upgraded to Marshmallow and it was even better than Lollipop. Faster, smoother, while having more features than ever before. My mother still uses a Galaxy S4 with Lollipop and it's still very useable. It's still smooth and responsive.
Now I have a 6P running Nougat DP5. Again, it runs very well. It's pretty much release ready at this stage.
Your distaste for the latest versions of Android are likely the result of having used some bad device which is simply not a fair way to objectively determine the quality of any software. It's like calling Windows bad because your trash $500 laptop with an awful screen and abysmal hard drive couldn't run it properly and then comparing that software experience to that of Mac OS X running on a $1500 MacBook Pro. Senseless.
Alternatively, if you were using a Nexus device I would assume that you have never cleared your cache or performed a factory reset if your device was running into problems such as rogue apps draining the battery or causing performance issues immediately after updating to a newer version of Android or even bothered to ask someone for help.
My opinion is that this is a grossly ill-informed post with absolutely no knowledge used to write it.
I honestly can't tell if this post is serious or not but it really got on my nerves.