Bale fell out of favour at Madrid after Zinedine Zidane returned for his second spell in charge in March.
But his lofty wages - reportedly as high as £350,000 a week - mean few clubs will likely be able to afford the Wales star.
Madrid have been spending heavily on reinforcements with France international Ferland Mendy their latest signing, the left-back joining Eden Hazard, Luka Jovic and Eder Militao in heading to the Santiago Bernabeu.
Manchester United have long been linked with a move for Bale, but reports suggest the Premier League side are no longer considering a move.
Calderon therefore feels a loan deal could suit both Madrid and Bale, who cost what was then a world-record £85million fee when he signed from Tottenham in 2013.
"His situation here is very difficult," Calderon told Sky Sports. "It is clear Zidane has discarded him in his mind.
"He showed that last season by not having him in the starting line-up. It is very disappointing for a player like him.
"Also the problem is the transfer fee. Real Madrid want to get a lot of money for him, but I find that difficult.
"Maybe the best thing for everyone would be a loan. The player could recover his confidence on the field and Real Madrid could see his value rise.
"He wasn't successful here for many reasons - injuries, also the handicap of the money. When he came we paid more than we did for Cristiano [Ronaldo].
"People thought he should be better than Cristiano but that is very difficult."
Hazard has become Madrid's latest 'Galactico' signing and the Belgium star will be presented by the club on Thursday.
But Calderon does not believe Hazard, who joined from Chelsea for a fee that could reportedly exceed £150m, can succeed Ronaldo either.
"[Hazard] is a fantastic player, but Cristiano is unique," Calderon said. "I've never seen or found a player like him.
"Hazard is very talented and skilful, he's proven that in the strongest championship in the world, which is the Premier League.
"He can play on both flanks, is a good dribbler with excellent passing. He can play in many positions - attacking midfielder, winger, even a false nine - so it is a fantastic opportunity."