I'm about 20 years short of qualified for this sub-forum, but I do wear knee braces when hiking because my knees are prone to bursitis/irritation because of patella alta (high patella). My knees act functionally much older than they are, so I hope can provide some insight from nearly 30 years of knee issues, physical therapy, and orthopedic evaluations.
For braces, I've found is that even the lightest neoprene McGuard brace (with kneecap cutout) helps keep the knees warm, mobile, and slightly more stable. Anti-itch foot powder is essential to keep the funk to a minimum in the braces and reduce chafing. Same for heavier braces as the ones linked above. I have a couple heavier McGuard braces with flexible rods instead of metal hinges that provide good support and some "spring" back from knee flexion. I wear them when packing heavy or hiking downhill.
Knee braces are obviously a "bandaid" on a potential problem that can be minimized through specific strengthening. I have found the following areas to work on in order of importance:
1. The best guard against knee injury is unilateral exercises that strengthen each leg independently, targeting stabilizers, adductors, and abductors. Knees are very strong when loaded as a pair, but off-balance, single-legged stresses are the largest cause of injury.
2. Secondly is strength with knees at greater than 45 degree flexion, trained with static exercises (wall sits, Spanish squats), and moving up to isotonic (slow) box squats. Finally adding in vertical jumps and dynamic lunges, and Bulgarian split squats. You don't need much more than bodyweight plus a backpack weight to be "strong," no need for heavy weights unless you want to.
3. Knee strength at full extension is also important to prevent hyper-extension. Isometric holds with full extension. Single-legged Romanian deadlift with a band pulling the standing knee outwards are one of my favorites, since they are unilateral and also work hamstrings/glutes.
4. Glute and hamstring activation. Consciously focus on activating these areas while doing the exercises above. Both stabilize and strengthen the knee joint.
5. Peripheral muscles. Strengthen the tibialis (toe lifts), psoas, glute medius, and learn to brace your abs when lifting heavy weight. All upstream and downstream strengthening will reduce contributing causes to knee instability.