No, usb3.0 is even slower.
Do not worry much.
The real value of a ssd is the random I/o service times, and that is unaffected by the slower sata speeds.
Do not be much swayed by vendor synthetic SSD benchmarks.
They are done with apps that push the SSD to it's maximum using queue lengths of 30 or so.
Most desktop users will do one or two things at a time, so they will see queue lengths of one or two.
What really counts is the response times, particularly for small random I/O. That is what the os does mostly.
For that, the response times of current SSD's are remarkably similar. And quick. They will be 50X faster than a hard drive.