Reginald Hargreeves is the reason that The Umbrella Academy can beat The Sparrow Academy in the upcoming season of The Umbrella Academy. The Umbrella Academy season 3 is set to premiere on Netflix on June 22, beginning where season 2 left off with a massive cliffhanger. The Umbrella Academy season 2 saw the adopted siblings stranded in 1960s Dallas, once again trying to prevent the coming apocalypse. Luckily, they managed and even found a way to return home to 2019 - but as a result of going to their father's younger self for help in the 60s, The Umbrella Academy inadvertently changed their fate and found themselves replaced by The Sparrow Academy.
As is clear from both season 1 and season 2 of The Umbrella Academy, Reginald Hargreeves (Colm Feore) was never a very nurturing father, using his power and brilliance as an excuse for neglectful and abusive behavior towards his children. He adopted each member of The Umbrella Academy because he wanted to form a team that would one day save the world, coveting them for their abilities and little else. Each member of The Umbrella Academy suffered at the hands of their father, though in different ways, depending on their gifts. The training regimen was rigid, and their upbringing was strict, which only served to prove how important it was that the siblings loved and supported one another - even if it took a while for them to understand one another.
The opening sequence for The Umbrella Academy season 2 culminated in Five (Aidan Gallagher) watching his siblings trying to fight off a Russian invasion just before a nuclear bomb hit Dallas and wiped everything out. What is interesting about this opening sequence is that it shows the true extent of each sibling’s power. Klaus (Robert Sheehan), for example, is shown to not only be able to communicate with the dead but control their actions as well, and Allison (Emmy Raver-Lampman) is shown to be able to control multiple people at once with her "rumor" power and cause their heads to explode as a result. This is more than Reginald Hargreeves or the Umbrella Academy siblings themselves ever thought to be possible, proving that Hargreeves' absence - and the absence of his restrictive training regimes and lack of belief in his pupils - will only make The Umbrella Academy stronger, and quite possibly stronger than The Sparrow Academy as well.
Reginald Hargreeves' training only ever realized the lowest level of each child's ability. Klaus could commune with the dead but was afraid to, Five could teleport with limitations (and Hargreeves refused to train him to travel through time, which is how he ended up stuck in the apocalypse alone for over 40 years), and Viktor (Elliot Page) wasn't even allowed to use his abilities, kept in line through a mixture of drugs, lies, and social separation. None of the members of The Umbrella Academy ever reached their full potential. That only began to change once Reginald had died, and they were stranded on their own, learning to use their abilities to their full extent so that they could save not only the world, but their siblings as well. Reginald's strict influence is what kept them from being their strongest selves, and this vicious cycle has likely been repeated now with Hargreeves' treatment of The Sparrows. As a result, this might give The Umbrella Academy a distinct advantage and may lead to them being able to beat the Sparrows in The Umbrella Academy season 3.
Though the Sparrows and The Umbrella Academy will have had different types of training because of their different abilities, there is a good chance that the Umbrella Academy will have a better understanding of what they can do than the Sparrows. Reginald Hargreeves' influence as a father and scientist may prove to be detrimental to the Sparrows in the long run, though audiences will have to wait for The Umbrella Academy season 3 to release on Netflix before knowing exactly how The Umbrella Academy may or may not manage to beat the Sparrows.