Makes sense.

Making aya without extra acid in the water should still end under 7 because of the plant material doing. Unlikely to end with a >7 pH.

That bodily cleaned taut feeling, nothing bloated, is golden
I think the properties of harmalas are only partial responsible for this. Thinking of the tannins and whatnot.

In the process of brewing (vine only), now able to back this up with numbers:
Start water: Brita filtered water pH excact 7.00
After 6 hours boil + cooling (no added acid!) pH 4.60