After watching Spain, my fears are lately: Spain & Barca = that's the only way how they know to play.
I guess in 2050, we will still watch exactly the same football from those two teams.
Do you know why?
Because it worked in 2010.
Things are not really as simple as you want to make them look imo. 2010 also didn't happen suddenly but was a result of a longterm planned work.
We can somehow agree that Barca could start to recruit different profile of players (from countries like France and Germany for example) short and mid-term if we'd want to change the way we're playing drastically (I'm talking about "normal" times not now when we don't have money to really do anything). But while this would look like we're trying to change something there is no guarantee things would work. It's acutally very likely we'd fail and be even in a worse situation we're now trying to replicate things that worked in the past over and over again and hoping for different outcomes we've got in most recent history. And to make this "new philosophy" work longterm it would mean changing the way kids in La Masia are playing too which would again take a lot of time.
NT is different as clubs though as they normally can't import foreign talents and have a limited pool of players they can work with (even in a country like Spain which produces tons and tons of players every year they are in the end all of similar profile). So how can you expect them to play different? Even if we can say that some of their modern day midfielders are more direct than Xavi and Iniesta so some small modifications of the system could be done but overall philosophy would still stay similar. Obviously none of the new midfielders comes even close to Xaviesta quality which is not surprising as they are two of the best midfielders ever and Barca/Spain were lucky to have them playing together in their prime years which will probably never happen again. They might produce a Xavi or an Iniesta in 40-50 years but it's almost impossible they'll get a Xaviesta ever again.
Anyway, back to the question what Spain is supposed to do? They're not France who have athletic players of African origin so they can play to their strengths. Nor are they like Germany who were always a hard working team (although they've produced a lot more technical players over the last decade or so - which again is a product of long term plan and work) with a never give up attitude which they are learning since they've made their first football steps as 6-7 years old kids. And they are also not a traditionally great defensive team like Italy. You can't change the way senior NT is playing over the night. No coach can come into the locker room and say to the players something like "forget about everything you've learned so far in your careers about possession football, we'll now start to play by defending deep and try to score from counters."
It's a longterm process and Spain has certain limitations here compared to other top football nations so it's only logical for them to continue betting on their supposed strength which is being technically superior to the opponents. Although that strength is not clearly as evident as it was a decade ago it still gives them better chances to succeed than doing something they've never done before or can't do. Spain can't "out-France" France, "out-German" Germany or "out-Italy" Italy (if you understand what I mean), they can only beat them by playing it the only way they know and can.
I mean if anyone has shown he doesn't care that much about possession football it's Lucho. During his time at Barca people often complained about him not having enough control over the games etc. But he had arguably the best attacking trio we'll ever seen at his disposal back then so he played to their strengths (well, unless Messi wasn't the real coach at that time
). It brought us short term success but this approach wouldn't work longterm. And now with Spain he has Morata, Ferran and Olmo instead of a prime MSN
so can't really try to do the same things even if he'd want to change something.
But clearly, all of this doesn't mean some of Lucho's decisions were not questionable at least. Even with clear limitations this team has (and some of them not being Lucho's fault. I think with a fit Ramos - yeah, I know he could still take him to Euros even if not totally ready to play if nothing else for his leadership which this team clearly lacks - and Fati this would be a totally different team) they could and should still do better.