Likes/Dislikes: Some interactions aren't blocked by saying no
If you do this with any other skill activity you receive a hidden trait called trait_SimPreference_NoOpinion_Activities_[SkillName] which sets chance of getting such a popup for that particular skill to 0. Different story when it comes to video gaming: Selecting "No" adds trait_SimPreference_NoOpinion_Activities_VideoGaming, the 0-multiplier however checks for Trait_SimPreference_NoOpinion_VideoGaming (which your Sim won't ever get during normal gameplay).
Edit: As for Gardening, none of the interactions which may trigger a like/dislike popup feature trait_SimPreference_NoOpinion_Activities_Gardening in their 0-multiplier requirement lists (only like/dislike traits themselves are listed there).
Edit By Crinrict: Adjusted Title as there was already a report for gardening here: Sim keeps getting asked if she likes gardening even after I say "no" | EA Forums - 11715564
Also please always add mod/cc tags and a platform even if you're on console or checked something in the files.
Archived thread had around 0 me toos