A bike should get disqualified from any sort of playful/nimble trait if it requires you to adapt to poorly balanced geo, IMO. By adapt, I mean the frequent need to get your body weight forward to compensate for poor front wheel traction, or weight back to compensate for non-gravity-friendly geo. Everything you use to define playful/nimble, like HTA, CSL, etc. gets thrown out the window once you are riding something technical on such a bike.
If your body weight is already in the right place for great front wheel traction, and confidence to plow, you can then be free to initiate whatever techniques you want from a strong ready position, rather than needing to return to that position from a forward/rearward or comfy pedaling one. Preferably, the comfy pedaling position is also the strongest ready position (seated position not too far from standing position, with steep enough STA). The bike becomes playful if you actively engage on popping off whatever feature that comes on the trail, since you don't need any extra time to prepare for it, like getting in the right position to not wreck yourself.
The key to this is essentially centering the rider in the right spot between the axles and/or tire contact points, and this often is dictated by where the BB is located. BB height, rear center (CSL) and front center (or WB minus RC), are the key geo figures to consider. BB drop is also worth considering, as the more BB drop you have, the more influence that weight on the cranks has on the axles, keeping it stuck to the ground (less reluctant to lift, or in other words, less playful). 60/40%, as exactly as possible, weight distro between rear and front is a great starting point (measured by scales under each tire).
In other words, this balance is what separates great bikes from bad* bikes (more like mediocre, because by my definition 99.9999% of bikes are bad). You don't want a bad bike that's playful/nimble, as it compromises its performance in tech. This is what the OP and many other shoppers are worried about. This balance is so delicate, that it's what you feel when you take the same bike in two different sizes out onto technical terrain that tests your traction, and techniques to maintain traction. The one that feels more intuitive (AKA natural, less complicated) to ride is the more balanced one. You don't have to adapt to the bike, you don't feel like you're a passenger holding onto something that you don't have full control of--instead, you feel like you're the rider, and you're the one guiding the tires with as much precision/resolution as you wish. When you're flowing on a good balanced bike, you can pump up the adrenaline and enter your "in-the-zone" mode and things might actually become slow-mo, as you time your moves precisely with twitch-like reaction speed. This doesn't happen on a bad unbalanced bike; you'd feel anxiety instead. Though, I guess relief can be interpreted as stoke, if you manage to overcome the anxiety/fear.
Depending on how in-tune you are with noticing this balance, what can separate a good bike from a bad bike is picking the right size. A Canfield Riot/Toir would feel great, maintaining its playfulness and nimbleness in all-around conditions/situations in small and maybe medium, but it's going to force you to adapt to poor front wheel traction in Lg and XL in the tech. This niggle might be easy to live with when you are still in your new bike stoke phase, but I bet once that fades, you're going to hope for a successor that addresses that niggle to get that perfection you imagine. That or you do some weird overcompensation, getting the most aggressive front tire and most supple fork you are willing to throw money at, and end up with a mutant that still has you looking for some better solution/compromise that you can settle with.
If you consider every individual size as a different bike, like a 2023 SC Hightower S, M, L, XL, XXL being 5 diff bikes, and I only consider the Lg to be great for someone 5' 11" and 145 lbs, you can see why I might consider 99.999% of bikes to be bad (for that one person; a med Hightower might suit someone 5' 10" and 190 lbs). Brands that adjust CSL according to the WB, might have 2 to 4 out of 5 sizes that I'd call great, like some Norco bikes (XS and S tend to not be great, on a vast majority of models). It's no wonder that people with decades of riding, and experience with dozens of bikes, who don't want to settle for something less than the best, still look for input from others to find the singular best choice out of 10s of thousands of choices, since many of us have gone on that journey as well, and have insight to share. We just probably don't have money to throw away to keep reiterating on what we learned.
It's not like you remain static on a great bike, it's more like you let the bike freely rock back-and-forth under you (not deathgripping all stiff-like, like a newb on a mechanical bull, but loose and confident). It's the bike that is pitching back (making you look aggressive), or pitching forward (making you look like you're rolling something steep), reserving your actual body movements for corners, jumps, line changes, etc. All you are doing is keeping your hands on the grips, standing on the pedals with knees bent a little, and scanning the terrain, saving energy for techniques that are either fun or meaningful. If we're overwhelmed with stuff to handle, like needing to be rearward just the rigggght amount to flow correctly, we'd be dragging brakes to give enough time to do so, which also means we need to compensate for the lower traction under braking and potential loose rocks that get dislodged from braking forces.
