Hard brick phone exchange and deleting data
Summing up from the (now purged) comments:

As the device really seems to be bricked beyond the chance of repairing it yourself, there are indeed only two options left: Keeping it as a paper-weight to protect your data – or sending it in under warranty/insurance to get it repaired, with the risk that someone might try to get a hand on your data.

While the latter is definitely possible, and there's no 100% guarantee against it, check the facts on how likely this will be: the harder it is (and currently, it looks pretty hard), the more valuable data one must expect to be on the device to consider the efforts worthwhile. If you were the president of "something big", or there were other reasons to suspect "top secrets" on the device, it would be one thing. But – no offense meant – the device of some "average user" hardly seems to justify it:


if the eMMC chip was really fried, it would require very expensive forensics work to recover even parts of the data
if the motherboard broke, considering the SoC design repair costs would demand to simply replace it. To get to the data, the chip would have to be unsoldered and placed on another board, or at least JTAGged (too much effort again)


So, no guarantees – but it's quite unlikely someone would care restoring the data. Not even as a special service to you – unless you're willing to include a bank cheque holding at least a 4-digit sum (in front of the decimal of course).