My sister-in-law’s son lives in Barcelona. Talking to him last week he was saying that there would likely be a majority for independence, but I didn’t get the impression it would be as high as eighty percent.
Ignoring what looks like a clear democratic decision is never politically easy. I can see why the Spanish government wouldn’t want such a clear position to be established. Maybe there’s an issue about whether, given the economic impact of secession, the whole of Spain should be allowed to vote on it ? The Catalans might want to jump ship but the rest of Spain might not want to let them. A (loose) analogy might be the question of making the rich pay more tax in times of economic hardship. It would ‘only’ sting the rich, so if this question was put to a referendum they might argue that they should be the ‘only’ ones allowed to vote on the subject. But poor people might feel that everyone should get a vote, even though not everyone is the subject of the policy.