I've had two different outfits, one was motorcycle jeans with knee/hip/kevlar and a Joe Rocket mesh jacket.
The 2nd was regular pants with knee/shin protection under it as a separate thing. Then hip/thigh/rear protection with off road mesh shorts.
On the outside, it's just regular pants, under them are independent products that protect certain areas.
I can slip off the knee/shin in seconds, it's just velcro. The thigh, hip, rear is a different story. It's like boxers with ABS plastic shields in spots.
I carry three cable/lock sets on the bike, one can go thru the jacket arm and around a fork. Another for the tank bag.
You get off the bike and you can have shorts/pants on, take off the under protection, lock up your jacket and you're done.
Here's one example, the shin/knee guards, the velco is about 2" wide, and holds well for about 1 year before it gets long and I had to stitch it up to get it tight again.
https://www.amazon.com/Shift-Racing-Enforcer-Adult-Motorcycle/dp/B00PQWCG6S
You can do the same thing with the "boxer underwear", by cutting it and adding thick velcro to the pads. Think of the velcro pads as something that just holds the ABS plastic in place. You'd be able to reach in and undo the velcro and pull out the ABS pads and be on your way.
You can poke a hole in the pads, run a cable/lock thru them so that nobody takes them.
I use these -- $18 on amazon. Love them. I'm sure your $44 ones in the link are better somehow... but I'm happy with em.https://www.amazon.com/gp/product/B00PQWCG6S/ref=ppx_yo_dt_b_asin_image_o04_s00?ie=UTF8&psc=1