Ignore ‘smaller userbase’ if you prefer it that way. We’re talking about it as a platform, in its UI, functionalities, etc.
I go first: You can post images in the text body with a simple Ctrl+V. No need to upload it somewhere or even save to your device.
So, in your opinion, in what Lemmy is better than Reddit already?
Lack of advertisements. Last time I used the official Reddit app it showed an advertisement every 5 posts or so. And of course no way to disable it. Good riddance.