It's not that simple. First of, Catalonians haven't actually voted for independence. Their first referendum resulted in a vote to stay, and the second one which independists claim proves 102% of catalonia wants to go independent is pure unadulterated bullshit. It wasn't officially declared at all (because the vote on the regional court failed, meaning catalonians themselves rejected it) then they culled participants, only letting their people in, did it without any observers, had discrepancies on the number of votes, and in general made this election look positively dashing. So while we indeed voted to give them the right to get out (and it passed) they first need to vote on their regional chamber to have a referendum, properly do it, have the result support their independence (good luck with that specially now that their GDP has plunged because of the last referendum), have the executive corroborate it, then the doc has to come to our general courts which have to pass the law themselves after negotiating the terms of the break (and since we're talking about changing the territory we're talking about actually changing the bloody constitution here, and good luck with that shit, you need a 70% vote for that and now that Vox got a chunk the right wing's gonna brick it on principle, no way the PP lets catalonia out now. They were willing to do that back in the day because they didn't have any nationalistic opposition anyway so their right wing vote was secure, but VOX is very open about not wanting anyone out for any reason.)
So in summary: we literally gave them a chance to do that. And they fucked it. And now with the new minor parties their chances of getting out now are basically zero.
^ What he says but unironically.
Actually Spain's GDP in 2019 was 1.244.757M.€ and Catalonia's was 236.739M.€, which is 'bout 19% of Spain's GDP. It was however about 1/3 at its peak... right before the referendum.
Reason why is that Catalonia's GDP has been bricked by the referendum. And reason for that is because Catalonia made its money by having outrageously low taxes (not quite a tax haven, but low enough and with so many bullshit "exceptions" that it might as well be in practice). They made their money by destroying the rest of the country's capacity to compete with them economically by abusing the power to control tax law the autonomies have, and using the bullshit amount of power our electoral law gives them to get a lot, and I do mean a FUCKLOAD of GIBBS from central gov, so much so that if you see the ratio of gibbs from central gov to catalonian project by the amount of taxes catalonia pays the central gov it would look like they are one of the poorest autonomies in spain, and rank nearly as low as some of the most impoverished provinces. And going so far as to actively sabotage laws trying to get our train infrastructure to be better so that other provinces couldn't compete due to cost of transport (due to their direct connection to france). Not that they needed to in the end, idiots didn't realice the Sauds had already bought the king to make sure that shit got torpedoed so idiots wasted political power and got everyone to hate them for no reason.
But when the central government said in no unclear terms that if Catalonia became independent we were absolutely gonna put the usual tariffs in that border, and their attempt at getting Merkel to favor them backfired with the Germans saying "nah he's right the EU won't be letting that shit go unchecked" most catalonian businesses suddently discovered that paying taxes has its benefits and either fled or started, ehem, "diversifying" (like Amazon is doing to Portland now) some to the rest of spain and the rest to france and britain. Practically stopping their growth dead in its tracks.
So yes, economically, we can absolutely push Catalonia out, and we'll be able to more and more every year as they have no way out of this hole until they stop being idiots, and this is catalonia we're talking about so... Fat chance, but in fact as we discovered when making the calculations back during the independence fiasco, WE WOULD MAKE MORE MONEY WITHOUT THEM. The amount of tax they don't pay and the amount of gibbs they get is so large that they currently cost us more than they benefit us, they are a literal tumor. So stfu with that bullshit boy because you're sounding just like Cuomo and are as wrong as he is.
Real answer as to why Catalonians don't wanna live is simple: independence was always a fucking smokescreen, they just use it to get more gibbs, but whenever it goes too far, like it did with the referendum and their gibbs and lack of border is threatened they push their heads straight up their asses and eat each other, they'll never go, and they'll always claim they're going to, because they have a bested interest.