@SquidWeaselYay, I'm still wondering what you do when you "try" to flex the boot, and what your purpose is in doing this "trying."
A boot flexes as a by-product of something else. That something else is the important thing. There are some very high level skiers who are in favor of boots that don't flex. That lack of flexion does not mean they are not forward enough. It just means... well, I'll try to get to that.
If your stance puts you on top of the skis in such a way that most of your body weight is hovering over the front of the skis, in front of your toe piece, then you are forward. If your boots are soft, then the cuffs will flex when the downward pressure from your hovering body increases in the middle of the turn, when forces are strongest. Your stance doesn't have to change to make that flexion happen. The cuff's flexion absorbs that mounting pressure. When it stops flexing, your ski's front end, the shovel, receives the pressure and it bends.
If you have stiff boots, the ski's shovel receives that mounting pressure right away, and bends sooner.
The flexion of a boot is there not for comfort, not to signal that you are forward, but to absorb some of that pressure before the ski responds. Boot flexion delays the bending of the ski's shovel.
Who would want the boot cuff's absorption to delay the ski's response?
1. People who are not yet precise with their pressure management (thus low flex numbers for beginners and intermediates who don't yet know how to manage pressure in a timely manner).
2. People who are skiing terrain or conditions that will produce irregular pressures that even a highly skilled skier can't manage properly (bump skiers).
3. Skiers in too-loose boots who need to avoid the shin-bang that comes from shins bumping into the cuffs since there's so much air space in there.
4. Skiers who like to make gentle, skidded turns, who do not necessarily want to pay attention to controlling the bend in the ski's shovel, who ski on nearly flat skis anyway and want a soft, gentle ride.
5. Skiers who are still building their edging skills, who don't want to be surprised by the effects of an inadvertantly bent shovel that suddenly comes around when they didn't expect or try to create that bend.
6. High level skiers who don't want boot cuffs to flex like the immediate response of their shovels to the mounting pressures. They manage that bend well in order to determine turn radius for their edged turns.
You are light in weight, so what a soft flexible boot means for you is different from a 145 lb skier. In any event, there's no reason to "try" to bend a cuff. If you are bending your knees to bend the cuff, stop. Just ski and start paying attention to how much the ski bends when your skis are pointing down the fall line and just afterwards (apex), not how much the cuff gives. It's the ski that makes the turn.