It's attention, not money, we should budget

In principle I agree with your premise. Execution is another element and for some the scale solidness when patients are tested and the perceived net result is not gained. The easier thing to do is throw money at the problem. 
I actually found that in my environment spending less on speakers was better. Around 20%. Moved that 10% to electronics and room 40/35 5% power and cables. 

30% room might be good if you have a dedicated listening room, but I think it's a bit much for a room that serves a multitude of purposes.... 

Maybe.  What if you keep the stereo in mind when selecting your home furnishings, and rugs, and maybe throw some panels on the ceiling?

My take…No doubt your room is very important.  Percentages are just a rough guide that may or may apply very differently to audio junkies.  They are most applicable to dedicated  room treatments or construction and may very minimally apply to living areas. Sooo many factors are involved that sku the percentages. In my living area working off a corner, valted ceiling, open access, built-ins, furnishings…very little can and needs to be done and it works out pretty well. Tried temp panels and drapery fabric with no improvement and ended up just using a bass trap in the corner behind my system.

Yikes… I know when shopping for home furnishings with my wife the stereo system does and will never take priority or even be considered or discussed.  i am enjoying my happy relationship and her tolerance as it is now 🤣.

1) Speakers and room

2) Speakers and room

3) amplification 

4) cleaning out the ear wax.

….everything else.

I agree....there is very little correlation between price and performance and clearly speakers make by far the largest difference, followed by the quality of the recording and then the other electronics.