It clearly states that, first of all, the cat was old. And, secondly, while it's not all that clear from the context whether this has any connection to the fact that the cat was old, beautiful things were more significant to her than any other things. In other words, as you said it yourself, she was more interested in beautiful things. That's literally all it says. No less, no more.

If it's the expression to mean something to somebody that confuses you, then it just means to be of a specified degree of importance to somebody or to be very valuable to somebody. For example:

This old toy car means a lot to me because it was a gift on my fifth birthday from my grandfather who never came back home from the front line.

It clearly states that, first of all, the cat was old. And, secondly, while it's not all that clear from the context whether this has any connection to the fact that the cat was old, beautiful things were more significant to her than any other things. In other words, as you said it yourself, she was more interested in beautiful things. That's literally all it says. No less, no more.

If it's the expression "to mean something to somebody" that confuses you, then it just means "to be of a specified degree of importance to somebody" or "to be very valuable to somebody". For example:

This old toy car means a lot to me because it was a gift on my fifth birthday from my grandfather who never came back home from the front line.

It clearly states that, first of all, the cat was old. And, secondly, while it's not all that clear from the context whether this has any connection to the fact that the cat was old, beautiful things were more significant to her. That's literally all it says. No less, no more.

If it's the expression to mean something to somebody that confuses you, then it just means to be of a specified degree of importance to somebody or to be very valuable to somebody. For example:

This old toy car means a lot to me because it was a gift on my fifth birthday from my grandfather who never came back home from the front line.

It clearly states that, first of all, the cat was old. And, secondly, while it's not all that clear from the context whether this has any connection to the fact that the cat was old, beautiful things were more significant to her than any other things. In other words, as you said it yourself, she was more interested in beautiful things. That's literally all it says. No less, no more.

If it's the expression to mean something to somebody that confuses you, then it just means to be of a specified degree of importance to somebody or to be very valuable to somebody. For example:

This old toy car means a lot to me because it was a gift on my fifth birthday from my grandfather who never came back home from the front line.