Here are two hypothetical situations that might clarify your blatant confusion regarding the usage of the word "sealion", and exemplify the usage of behaviour instead of "intentions" to demarcate sealioning.

Situation A:

• [You] Damn, a glass of water after work is great.
• [Alice] You're drinking water. Water is poisonous.
• [You] No, it is not. Stop making stuff up.
• [Alice] Okay, but don't whine afterwards when you get poisoned.
• [Alice leaves]
• [a day passes by]
• [You] I was drinking water yesterday, and it was great.

Situation B:

• [You] Damn, a glass of water after work is great.
• [Bob] You're drinking water. I'll have you know that water is poisonous.
• [You] No, it is not. Stop making stuff up.
• [Bob] Why are you so aggressive? I'm just informing you.
• [You] No, water is not poisonous. Water is safe. It's good for you. Please stop wasting my time.
• [Bob] Do you have any evidence to back up your claim that water is safe?
• [You] I'm busy drinking my water. Can you excuse me?
• [Bob] I shall return later.
• [a day passes by]
• [You] I was drinking water yesterd...
• [Bob] I see that you're mentioning that poisonous substance again. I don't understand, why someone would harm themselves? I'm so confused...
• [You] Bob, fuck off.
• [Bob] Apparently you lack arguments to defend your outrageous claim that water is safe to drink. Such lack of rationality, I'm just trying to have a friendly conversation and inform you on the risks of the substance that you're ingesting.

Even if both Alice and Bob are conveying the same stupid discourse ("water is poisonous"), only one of them is sealioning - Bob. Why?

[Feel free to analyse this through mind/intention/etc. or behaviour. Refer to the sealion comic for reference.]