I don't necessarily agree with that. I've spoken that there can be an applicable model to consistently try and stay at this level before.
We have the right coach now in Pimienta and a bigger transfer budget than the majority of the LaLiga2 clubs to maintain a good level development+Results team in that category with signings.
You look at the Barcelona B team from 10/11 to 14/15 that maintained 4 seasons in LaLiga2 (2 top 4 finishes) when LE and Eusebio managed and we developed some great talents with smart signings that went onto good things.
In hindsight we had really good players come through (to be sold with buybacks when they had upside) and made some recruits who could of also made it as squad options (after being sold with buybacks).
First, it isn't just Barca, most of other clubs like Bilbao/Seville/Villarreal etc had a terrible time developing their talents in comparison to 3rd division. On paper it is an interesting theory but not in reality.
La Masia:
Fontas (LaLiga career), Muniesa (Premier League), Bartra (LaLiga), Sergi Gomez, Montoya, Sergi Roberto, Oriol Romeu (Premier League), Thiago (Bayern), JDS (LaLiga career), Rafinha (LaLiga career), Tello (LaLiga/Serie A), Grimaldo (Benfica), Gerard Delafeu (Watford), Xavi Quintilla (Villarreal), Adama Traore (Wolves), Sanabria (Serie A), Sandro (Valladolid), Munir (Sevilla),
Let's look at some names here:
Thiago: He has developed in 3rd division, not Segunda. Like at all. He has played 2 (and called for some games during Pep season with 4th division) with Barca B at 3rd division. In his last year he played 11 games in Barca B and 17 games with 1st team. Segunda had almost zero impact on his development.
Fontas: developed for 2 years with 3rd division too btw. Then he got with Segunda and we overrated him. He didn't have much success as a player.
Muniesa: Our best CB prospect since Pique, some even argued he was even better prospect. Failed to play in better team than Stoke. Didn't start half of games in a single season in 1st division football, he is for sure not a positive example for B team in Segunda. But hard to judge due to his injuries.
Developed 2 years in Segunda after one year in 2nd division, 4 years with Barca as last resort CB. Finally as a developed prospect he managed to be a true first team player in Germany and midtable club in Liga.
Segi Gomez & Montoya: another journey men who had decent career in smaller clubs or average in lower clubs.
And the problem is right there, in Segunda you develop dozen of players for average Liga teams. You get only one end of the bench player like Bartra or ultimate squad player like Roberto.
From 3rd division, we got almost all of our golden generation from Puyol to Thiago. Through almost a decade and half of work.
When in Segunda, coach has to take care about winning in addition to developing players. Munir/Sandro/Deulofeu never really had the chance to develop to their best while having to care about winning in tough competition with no player older than 24
When we returned in 17/18 we failed because we made the wrong signings with the wrong coach (Gerard Lopez), then panic signed in Winter poor players.
But now with Pimienta we have the right balance of development and results to develop players well at Barcelona B.
A quick reminder, Lopez had 2 successful years in even tougher conditions (transfer ban) in which he rebuilt the whole team and lead us to promotion. At this point he had more success in more difficult terms than Pimenta.
In Segunda, he was suddenly exposed as bad coach and left with fans cursing him.
Has this happened before? Yeah with Eusebio himself. After 3 good years he was laughing stock of Barca fans in his last year. Same for Vinyals who has just won us Youth UCL and then his Barca days ended after a trial with Barca B. I mean how would you know Pimienta will be any better?
Benefits: Better opposition, better away pitches, Less farmer tackling, Less Non-Eu Visa complications, Better signing's capacity.
Draw backs: League way too strong to develop players, coach will inevitably has to prioritize winning to keep his job rather than committing a career suicide, trying to develop our players in less winning culture.