numerous slowing effects do not count as "Slows" for slow potency reduction/immunity

Since the start of early access, there are number of effects that slow the player even with Slow Immunity from Pathfinder or Wanderlust's "Your speed is unaffected by Slows".
Is this the intended behaviour? As in you do not want the slow immunity to work on Zarokh's "collect" phase etc.

Another example is the "Quicksand" debuff caused by the Scorpion boss/devourers is an exception and still slows the player. There are many more debuffs that work through the "slow" immunity.

Could you please clarify if it is just bugged or these exceptions are made to slow you intentionally?

examples of debuffs bypassing reductions/immunity:

Temporal Bubble
"Web Slow" from Black Strider
Drowning orbs