rack investment is a relative thing to where you are on the system building path. no one size fits all.
1-to begin with put your gear on the floor and invest your money in the best pair of speakers you can afford. that is the quickest path to the best sound. if your significant other wants the gear on some nice piece of furniture don’t worry about it too much.
2-as your system improves the most cost efficient rack approach is to get a basic rack and treat the individual chassis with footers to isolate the gear from resonance. but here it gets complicated because your floor is always a part of the rack equation as far as performance. so look at it as floor+rack=result.
3---past a certain point where you have your speakers and gear selected, with decent signal cables and power cables, next is your acoustics, power grid, and then rack performance.
so rack issues are not top of list, but they are on the list as you try to optimize your system. better acoustics, amps, sources, cables and power grid will take you farther in performance than a nice rack. until you deal with those other things first, a pretty sexy rack is assets miss-placed. a reference rack is very expensive, and very hard to sell or ship. so make sure your system is mature and settled before you take that step. treating individual components with footers (maybe DIY footers) might get you by and you can avoid an expensive rack all together.
i have a mega buck system and use basic racks at the highest levels of performance. but i also have some superb active isolation, just not expensive racks.