Yes im aware that everyone is an individual, that being said it seems to be a trend from what i see that ISTPs feel a deep empathy at certain times. T's alot of times seem quite serious to me and try to keep their emotions inside. According to this video by davesuperpowers
ISTJs are external feelers but it is their least used cognitive function (feel free to correct me if i misunderstood that from the video) where ISTPs are internal feelers. Yet from the ISTJs ive met there seems to be a lack of empathy. What have you witnessed?