(I've lived in Portugal more than 20 years ago and things (i.e. laws) might have changed significantly.) The problems with abandoned, degraded but historical/beautiful buildings had to do with several factors.
One factor was the social protection that renters (especially elderly) are afforded by law, especially keeping rents very (and I mean very low). This protection is in itself a good thing, but the downside was that landlords had no incentive to do renovations in the order of million euros for a building full of renters paying fifty euros per month each (I can't recall exact quantities). As I said, the protection of elderly is a good thing, but a balance was never achieved.
Another factor (and this ties with the bureaucracy theme) was that for some buildings, the state and municipality couldn't even locate the owner. So you might have this grade I building with a name as the legal owner, but it could be someone that emigrated to Brazil 50 years ago. Couple that with the slowness of judicial process and the building is in a limbo state for a century.
One factor was the social protection that renters (especially elderly) are afforded by law, especially keeping rents very (and I mean very low). This protection is in itself a good thing, but the downside was that landlords had no incentive to do renovations in the order of million euros for a building full of renters paying fifty euros per month each (I can't recall exact quantities). As I said, the protection of elderly is a good thing, but a balance was never achieved.
Another factor (and this ties with the bureaucracy theme) was that for some buildings, the state and municipality couldn't even locate the owner. So you might have this grade I building with a name as the legal owner, but it could be someone that emigrated to Brazil 50 years ago. Couple that with the slowness of judicial process and the building is in a limbo state for a century.