Viceidol It's a long time since he lived there. (It suggests "He
does not live there for a long time.")
It's a long time since he has lived there. (It suggests "He lives there for a long time.")
Are you sure that you copied those right-hand sentences correctly? Neither of them is good English, except, unusually, in the context of a present-tense narrative, which I can't imagine is the intention here (and in any case would not lead to correct interpretations of the sentences in italics).
To me, there is no material difference in meaning between the two sentences in italics. Both mean that he used to live there, but he left a long time ago and does not live there now.
More generally, though, the simple past means that we're referring to a single instance of whatever activity it is, and the perfect tense tends to suggest several instances or a pattern of behaviour. This difference is of little importance with the verb "lived", but in other cases it can be more apparent. For example,
It's a long time since he's visited America. -- Suggests that he previously visited America several times, perhaps regularly, but that this pattern of behaviour stopped a long time ago.
It's a long time since he visited America. -- Means that it's been a long time since that last specific visit. (Note, though, that it's quite possible to use this form even if he used to visit regularly, because there's always a last specific visit.)