From that 538 chart, the Cavs’ strength of schedule of 8.6 is the highest by a good margin. MJ’s teams won their matchups by greater margins, but the difficulty ratings on those matchups were, from 1991-1998: 5.2 (60% of the Cavs’ 8.6), 6.0 (70%), 5.7 (66%), 5.2 (60%), 7.4 (86%), 7.3 (85%).