I turned on the "sponsored links" option when I came across it because I usually like Firefox (though the new tabs UI look has me extremely disappointed) and I figured "what the heck", if it helps, why not? I didn't know where they were going to show but I definitely didn't think they would be inserted on my shortcuts on my new tab page. 😕
I don't mind a link to Amazon and Temu and whatever, heck I'd use it if it applied to me (I use Amazon just not the American one)...but not when it's going to displace my own shortcuts and eat up slots. I'm use to things being in a specific spot, suddenly inserting links at the top pushed everything and messed up my organization.
So I'm just here to suggest: if you want to put sponsored links in the new tab homepage, sure but maybe give them a dedicated spot. As it stand I turned the feature off.