Totally. I use Lyft wherever I can but I can virtually always use Uber whereas Lyft is spotty.
I travel regularly and it is very rare not to have Lyft available. Virtually any city with >250k has both from my experience, although that could just be where I travel, I don't know.
Everywhere other than the US and Canada?
Lyft is US/Canada only, while Uber is much more global.