Forget snow leopard, Apple can't even keep compatibility for the version they released 1 year ago.
When Apple announces a new OS update at WWDC you have approximately 4 months to install a beta on an external drive and fix any incompatibilities. Oh and it's a moving target, they only freeze it just before release. This process repeats every single year, sometimes they are so excited to break shit that they do it in a patch release but that's much rarer.
If there's a silver lining it's that Apple has gotten so bored with the Mac that they don't change as much as they used to, it's certainly not as bad as it used to be, but not because Apple has suddenly started caring about backwards compatibility.
When Apple announces a new OS update at WWDC you have approximately 4 months to install a beta on an external drive and fix any incompatibilities. Oh and it's a moving target, they only freeze it just before release. This process repeats every single year, sometimes they are so excited to break shit that they do it in a patch release but that's much rarer.
If there's a silver lining it's that Apple has gotten so bored with the Mac that they don't change as much as they used to, it's certainly not as bad as it used to be, but not because Apple has suddenly started caring about backwards compatibility.