All non diesel turbo engines are unreliable when compared to non turbo, so it depends what you mean by “reliable”.
They’re unforgiving of heat, non synthetic oil, extended oil changes. Even a minor oversight means needing a new block (which are in high demand)
By now a 2005 has a long unknown history.
If they’ve got a known documented history of maintenance, never been run hot, synthetic oil changed very frequently, and taken care of, and it’s never eaten a turbo or turbo replaced with a cheap aftermarket garbage….they can a decent vehicle.
Practically that almost never happens. So yes they’re reliable but no you probably won’t find one in the condition I described.
It also needs Subaru timing belt pulleys tensioner and water pump no matter what it’s timing belt history. It’s probably old or has aftermarket parts or the pulleys and tensioner have never been replaced. “New timing belt” isn’t good enough. Has to be Subaru or AISIn and all new pulleys too.