The bug
Projectiles on fire don't melt powder snow when thrown at high speeds from certain distances. This also affects dispensers throwing projectiles.
Linked issues
relates to
Attachments
Comments

You are right, it seems to have more to do with the projectile's speed and how distant it is from the powder snow block.

It looks like your experiencing MC-213791 does that describe your issue?

I think it has the same cause, but is not the same issue.
That ticket describes powder snow not extinguishing the projectiles, while this one is about the powder snow block not being destroyed. Also, that issue was last updated on 21w06a, while the ability for entities on fire to destroy powder snow was added on 21w13a.

Also, it seems very interesting that projectiles on fire used to be sometimes extinguished by powder snow. That does not happen at all anymore.
Edit: that was reported separately at MC-245603.

It's similar to MC-92875

Affects 25w02a.
Also, the wording on this ticket seems to imply the distance traveled has any impact on the bug. I only observed it being affected by velocity and angle.
The issue here is that projectiles on fire sometimes do not melt powder snow when travelling at high speeds. The angle at which the projectile is shot into the powder snow does not matter. I can confirm that this is an issue with that being said.