Yes, there are metrics. I guess the one I like is the Extra Bases Taken Percentage -- in conjunction, of course, with Outs On Base. Paul Goldschmidt has the reputation for great baserunning. Last year he stole just one base on one try, but his Extra Base Taken Percentage was 55 percent, which tied his career high. By comparison, Harrison Bader came in at just 21 percent.
This would be a good topic to dig into. There are a lot of cool metrics that prove whether or not a baserunner was so good as to be invisible -- as the Cards broadcasters used to say about Albert Pujols.
For a slow guy, Yadier Molina can steal some bases by being sneaky but taking extra bases is obviously hard for him. His percentage came in at 6 percent last year, down from 33 and 32 percent the prevous two years.