What? No. That's not the TL;DR at all. AES in XTS mode wasn't performant enough. Speck in XTS mode was a candidate, but it had a very dubious background. So,

What? No. That's not the TL;DR at all. AES in XTS mode wasn't performant enough. Speck in XTS mode was a candidate, but it had a very dubious background. So, instead they developed construct based on existing trusted primitives that is faster than both AES-XTS and Speck-XTS on the target hardware.