Well what would be the difference between a mage and thief of light when it comes to information. I keep hearing that a thief of light will only share information when it benefits them. But a mage of light would be the pwrisnt to go to for all the information. Would a thief of light enjoy simply talking/explaining things to anyone who wants it because the thief wants to give exposition ( no strings attached )

The difference is that a Mage takes the information to learn about it, they want to Know things, whereas the Thief wants to make use of the Information. Light is a messy Aspect because it conflicts with the Know Classes- If you have Info, you Know about it after all. But the Thief gathers it for a purpose, where a Mage may only want to know for the sake of knowing, or know intrinsically and put it to use, not because it’s their main purpose, but because they already know about it enough to put things in motions.

Not to say, Light means more than Information, so a good chunk of what they do could be relating to other things with Luck. Think about it this way- Rose gathered information about the Alpha Session and offered exposition about it to Dave to be prepared for what was to come, and just have a general idea of the situation. In turn, Vriska gathered information about the Retcon Timeline and formulated a plan based on it- And failed completely because she disregarded the details and importance of what was going to go down in various different places.