As the title says, is it okay to include CC in lots that are going to be uploaded? Because someone on Reddit is asking me to download a lot that I uploaded there yesterday, which I said yes (what I uploaded there are just pictures of the lot). Then I decided that I would upload the lot here in MTS. But I'm unsure if the lot to be uploaded should still have its CC on it.

If the creator allows it. Most creators have terms of use (TOU) on their CCs, so if it states that you can include them on your lot then you may do so, otherwise don't. However, there are some creators who have no clear TOU so presumably they would allow it? Also if the download site (or link) is already gone I guess it's kinda safe to include them, in my opinion.
More info here:
https://modthesims.info/rubrics/4143/