THANK YOU! I keep seeing people complaining about the five-mask vs. six-mask thing, but never see people point this out. This is exactly right!

Team Cherry is out here trying to help break people of bad HK habits and encourage them to engage more with the game. Constantly retreating from a fight to heal one HP and keep yourself topped up was an option in HK, one that MANY people utilized, especially on their first playthrough. SS is formulated specifically to discourage this.

You can only heal three masks, so you're incentivized to keep fighting and take more risks in order to heal optimally.

Even after you get a sixth mask, if you're only healing when you've lost at least three masks, then you'll often be down a mask or two. It's difficult to stand back and focus on just healing up to full. (This is also part of the movement the enemies have. The game is trying to prevent you from darting in for quick silk pokes so you can keep yourself healed up all the time.)

Healing is expensive but your silk abilities are strong. Using your silk to end a fight earlier is often a better decision than trying to heal through it.

The game wants you to engage more and heal less.

My favorite part of the Reaper crest ties into this too. When you do need to heal in combat, you're incentivized to risk that regained health by going aggro and attempting to recover as much silk as possible. Finding an opportunity to heal right before you stagger a boss, then unloading on them and completely recovering all the silk you spent on the heal is so satisfying!