It’s difficult to quantify personalities and this is especially so with the contradiction that is the ISTP. They tend to not do half measures and so trying to assess if someone is such a personality type will depend if you experience the full on, jump in, thrill seeking ISTP or the withdrawn, apparently disinterested ISTP, ie on which ISTP you get.
The STP desire to store knowledge and apply it practically right here right now is compounded by Introversion: so while the ESTP will live a life full of jumping from one exciting adventure after another, the ISTP will be more likely to jump into the adventure, butt out completely and utterly, then, like Clark Kent putting his suit on, throw himself into the action.
This anomaly also manifests itself in the level of detail that the ISTP becomes immersed in. They work in such short bursts of frenetic energy and so will either be right into the weeds of detail, or floating way above. Unlike the ISTJ who will work steadily and predictably towards a known conclusion, the ISTP will wait until the action starts and then, using all the knowledge, experience and expertise amassed over the years, bring all this to bear on the problem, before disappearing once the action is gone and the job becomes steady. Yet they are capable of being incredibly detailed, but this needs to be applied specifically and practically, solve the problem and move on a bit like Clint Eastwood’s character in High Plain’s Drifter: “where did he come from…where has he gone?” Well the job is done and he needs to wait until the actions starts again, that’s what energises the ISTP: full on or full off.