gravity magnitude ignored in 1.26.52 — only the sign is applied, with a fixed large magnitude

Custom projectile entities ignore the configured value of the gravity field in the minecraft:projectile component. Only its sign appears to be read, and a fixed large acceleration is applied:
Any positive value — even 0.0001 — produces the exact same heavy ballistic arc as the default (0.05).
0 also produces the same arc as the default.
Any negative value — even -0.000001 — launches the projectile steeply upward, also with a fixed magnitude unrelated to the configured value.
Additionally, anchor is ignored: the projectile spawns at the shooter's origin (feet) even with anchor: "eye_height".
Steps to reproduce: attach the minimal entity definition below, have any shooter fire it, observe the trajectory with different gravity values.
Expected: gravity applies proportionally to the configured value, as documented ("downward acceleration in blocks per tick squared").
Actual: magnitude is discarded; only sign is honored.
Regression note: the same projectile definition flew with a flat, near-straight trajectory in versions before the 1.26.20 Custom Projectiles changes; all custom projectiles broke simultaneously.