It depends on what platforms you're planning to release your game to.
For example, If your game is planned for android devices, go for a lower resolution as 1440p isn't that common, only new flagship phones have that, and you don't want to aim for those only because they're not a big % of the market.
If your assets are vector (not pixels) I'd recommend you to go with 1280x720 as that's a common resolution, and for the phones that have a different aspect ratio, you can use Fullscreen (Scale-outer/Scale-inner) depending on your game and/or preference.
This might seem frustrating at first but after you understand how it rolls, you'll get used to it.
Even if you're planning to release it on PC, 1440p is not ideal, yet.
You can read some useful information about this in Ashley's tutorial. (Which I can't link, on mobile)