Context is important with those comparisons. Goku had no emotional investment in defeating Metallic and conserving stamina was important in each of those battles, the latter two in which he was far more mature than his teen self. Against Yajirobe, Goku had just eaten a full meal to make stamina conservation irrelevant and was very emotionally invested in killing Tambourine. The fact that Yajirobe was also more durable than anyone else he encountered would also support him being close to Tenshinhan's level and Goku using his full power, unless you believe Goku had gained such a Zenkai his more casual self was on par with his 22nd TB battle level.