Can players react to a permanent (unit or gear) being played, and can they react to its triggered abilities?

Ruling: When a permanent (unit or gear) is played, it creates a 1-long chain that cannot be reacted to. However, if the permanent has a "When I'm Played" triggered ability, that ability lingers on the chain and allows for reactions.

Sequence:

• A vanilla unit or gear enters with no opportunity for reactions
• If a unit has a "When I'm Played" ability, that triggered ability creates a chain
• Players can react to the triggered ability, starting with the person who owns the ability

Nuances:

• The distinction applies between the permanent entering play (no reactions) versus its triggered abilities (reactions allowed)