Thanks. I agree with most of what you say.

> This is largely an issue of apostolic succession

There are two different cases here. Protestants differ in their ecclesiology; some retain belief in episcopal apostolic succession, others reject it. Of course, those Protestants who reject episcopal apostolic succession, there are (from the Catholic viewpoint) no valid bishops, and hence no valid priests, and hence no valid Eucharist. On the other hand, the Anglicans, and some (but not all) of the Lutheran churches, claim to have bishops with valid apostolic succession. In the case of the Anglicans, the Catholic Church has decided that their eucharistic theology is so different that their episcopal consecrations and ordinations are invalid as a result (Apostolicae curae, 1896). Presumably, the same judgement would apply to other Protestant denominations claiming episcopal apostolic succession also.