Originally Posted by
KerryIrons
Actually, low pressure reduces wear because it spreads the scrubbing force over more rubber. It can result in casing damage due to excessive flexing and the tire getting compressed against the rim.
That's a debatable comment but I meant that it looks like this tyre may have been running with an unusually wide, square contact patch i.e. at very low pressure. This may or may not be the reason for the sidewall issue. But since it's an isolated patch of damage, it's probably damage from road debris or perhaps a kerb.