I am not aware of research which counters this but will share a link to a summary found on the Davidson Database, for any who may be interested in a "Cliff's Notes" or "Spark Notes" quick overview for the work and conclusions of Miraca Gross: Exceptionally Gifted Children: Long-Term Outcomes of Academic Acceleration and Nonacceleration

A few brief excerpts
Surprisingly, given the wariness with which Australian teachers regard acceleration, 17 of the 60 young people were radically accelerated. None has regrets. Indeed, several say they would probably have preferred to accelerate still further or to have started earlier. Lubinski, Webb, Morelock, and Benbow (2001) report similar findings from a study of profoundly gifted SMPY accelerands.
In every case, the radical accelerands have been able to form warm, lasting, and deep friendships. They attribute this to the fact that their schools placed them, quite early, with older students to whom they tended to gravitate in any case. Those who experienced social isolation earlier say it disappeared after the first grade skip.
The five young people who accelerated by 2 years report as much, or almost as much, personal satisfaction with their education as do the radical accelerands although, like the radical accelerands, the majority say they would have liked to have been accelerated further.
However, those who were retained with age peers until fourth grade or later tend to find socializing difficult. Exceptionally and profoundly gifted students should have their first acceleration in the early years of school before they experience the social rejection that seems to be a significant risk for such students retained in mixed-ability classes. The skills of friendship building are first learned in the early years of school, and children who are rejected by their peers may miss out on these early and important lessons in forming relationships.
The five young people who were permitted a single grade advancement are not deeply satisfied with their education. Their school experience has not been happy, and they would have dearly loved to have been accelerated further. After the euphoria of having new, challenging work, school became just as boring as it had been before the acceleration.
The remaining 33 young people were retained, for the duration of their schooling, in a lockstep curriculum with age peers in what is euphemistically termed the “inclusion” classroom. The last thing they felt, as children or adolescents, was “included.” With few exceptions, they have very jaded views of their education. Two dropped out of high school and a number have dropped out of university. Several more have had ongoing difficulties at university, not because of lack of ability but because they have found it difficult to commit to undergraduate study that is less than stimulating. These young people had consoled themselves through the wilderness years of undemanding and repetitive school curriculum with the promise that university would be different—exciting, intellectually rigorous, vibrant—and when it was not, as the first year of university often is not, it seemed to be the last straw.

Some have begun to seriously doubt that they are, indeed, highly gifted. The impostor syndrome is readily validated with gifted students if they are given only work that does not require them to strive for success. It is difficult to maintain the belief that one can meet and overcome challenges if one never has the opportunity to test oneself.

Several of the nonaccelerands have serious and ongoing problems with social relationships. These young people find it very difficult to sustain friendships because having been, to a large extent, socially isolated at school, they have had much less practice in their formative years in developing and maintaining social relationships.

Possibly also of interest:
- Forum discussion threads on acceleration pros and cons
- Forum discussion thread on what children don't learn if not provided with appropriate academic challenge which requires effort
- Article excerpt: children need academic/intellectual peers
- book: Exceptionally Gifted Children 2nd Edition , Miraca Gross (2004), as seen on Amazon, which offers a "Look Inside" feature