This is because the (conjugated) verb is always the second idea in a sentence/it comes in second position. „Ich bin das“ - „Das bin ich“ - „Letztes Jahr bin ich das auf dem Foto gewesen.“ The second idea in all of these sentences (the second grammatical entity, not necessarily the second word) is the verb. The subject of the sentence is „Ich“, therefore we use „bin“. In English, „me“ is the object and „this“ (it) is the subject. That’s why we use „is“ and not „am“.

I think Jian referred to the question of why the conjugation in German does not follow the same pattern as in the English sentence. It’s not about word order (but, at first, I also understood the question the same way you did).

The verb *does* follow "das", doesn't it?