A topic from AEG's L5R CCG Rules forum, copied for Oracle of the Void from a copy of the forum saved in October 2015, so pages it didn't save are missing. Players' names are left out; the rules officials are named. Rulings are as they stood on these dates; later rulings, the rulebooks and the Rules Archive may differ.
A player, 14 February 2008
Stronghold Effects, targeting and costs applied to "cards" do not apply to a Stronghold unless they specifically mention the word "Stronghold." However, Strongholds count as cards in all other ways. Example: An effect that says: "Name a card. Abilities on cards with that title can not be used" does not apply to Strongholds because it is a non-Rules effect on the Stronghold. Example 2: A Reaction trigger states "After an effect from another player's card targets one of your cards:" This can be used in reaction to another player's Stronghold effect because the Stronghold's effects come from a card. It can also be used in reaction to another player targeting your Stronghold, because the reference itself is not an effect, targeting or cost.
The Death of Ryoshun This card remains in play in your home. Open: Discard this card: Name a card in play. Until the beginning of your next turn, actions on cards with that title may not be used.
Given the new rules regarding strongholds, can I name a stronghold when I use Death of Ryoshun?
Martin Lund (rules official), 14 February 2008
Stronghold Effects, targeting and costs applied to "cards" do not apply to a Stronghold unless they specifically mention the word "Stronghold." However, Strongholds count as cards in all other ways. Example: An effect that says: "Name a card. Abilities on cards with that title can not be used" does not apply to Strongholds because it is a non-Rules effect on the Stronghold. Example 2: A Reaction trigger states "After an effect from another player's card targets one of your cards:" This can be used in reaction to another player's Stronghold effect because the Stronghold's effects come from a card. It can also be used in reaction to another player targeting your Stronghold, because the reference itself is not an effect, targeting or cost.
The Death of Ryoshun This card remains in play in your home. Open: Discard this card: Name a card in play. Until the beginning of your next turn, actions on cards with that title may not be used.
Given the new rules regarding strongholds, can I name a stronghold when I use Death of Ryoshun?
No. Death of Ryoshun is nearly word-for-word the example used in the text you just posted of an ability that doesn't interact with a Stronghold.