‘Don’t take yourself so seriously’: what does this mean?

I found this  explanation online.

When used as a saying against you like, “you take yourself too seriously” it means in the speaker’s eyes that you are being one or some combination of the following:

A) Pretentious, in other words everyone wants distinction/merit/care but you’re trying to win it forcefully through your behavior/comments you make about yourself and they don’t really want to hear it, they got themselves to worry about afterall.

B) You’re being self-righteous in their eyes, in other words you’re very sure of yourself and how right you are, this rubs some the wrong way because we’re a social species and they want you to sacrifice some of you for them or go with the group, if you have a strong sense of self identity they aren’t getting what they want from you so credit it to a character flaw of yours stating your reasons for it are a flaw or just casting your self assurance as a negative quality, which by itself at least it isn’t.

C) They wish to influence you to do something, and they figure it’s a good angle of attack after they tried softer methods especially if you have a habit of being thoughtful/serious about stuff, they can try to use shame to then get what they want from you.

D) They genuinely think you’re miserable and want you to cheer up it’s bringing them down or they are concerned about you, or both.

When used as a saying like “you shouldn’t take life so seriously”, it instead usually means that they wish for you to lighten up, have fun, laugh a little, join in their fun, in other words they want you to have fun with them or not make them feel bad for them trying to have fun.

I found this  explanation online.

When used as a saying against you like, “you take yourself too seriously” it means in the speaker’s eyes that you are being one or some combination of the following:

A) Pretentious, in other words everyone wants distinction/merit/care but you’re trying to win it forcefully through your behavior/comments you make about yourself and they don’t really want to hear it, they got themselves to worry about afterall.

B) You’re being self-righteous in their eyes, in other words you’re very sure of yourself and how right you are, this rubs some the wrong way because we’re a social species and they want you to sacrifice some of you for them or go with the group, if you have a strong sense of self identity they aren’t getting what they want from you so credit it to a character flaw of yours stating your reasons for it are a flaw or just casting your self assurance as a negative quality, which by itself at least it isn’t.

C) They wish to influence you to do something, and they figure it’s a good angle of attack after they tried softer methods especially if you have a habit of being thoughtful/serious about stuff, they can try to use shame to then get what they want from you.

D) They genuinely think you’re miserable and want you to cheer up it’s bringing them down or they are concerned about you, or both.

When used as a saying like “you shouldn’t take life so seriously”, it instead usually means that they wish for you to lighten up, have fun, laugh a little, join in their fun, in other words they want you to have fun with them or not make them feel bad for them trying to have fun.

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