Sony's reason makes sense.
Last week at E3, the biggest video game expo in the US, Fortnite publishers announced their game would be heading to the Nintendo Switch. While cross-platform play between mobile devices, the Xbox One, the Nintendo Switch, and PC has been integrated into Fortnite, Sony was not willing to play nice with others. Sony stopped cross-platform play from being implemented on their PlayStation 4 system, and gamers were met with an unpleasant surprise when they tried to transfer their Fortnite accounts from the Sony system to the Nintendo Switch. Not only did Sony block gamers from transferring their accounts, but if players tried to sign on to their Switch in Fortnite, they were locked out of the game on both systems.
Sony never warned gamers that transferring their accounts would cause a lockout, which was perceived by many as a deceitful move. Their response to the situation was lackluster as well, and it neither assisted gamers with their locked out accounts or confirmed why they wouldn't join the cross-platform party along with other gaming systems. According to Business Insider, former Sony Online Entertainment president John Smedley, now general manager of Amazon Game Studios, had an explanation for the lack in cross-platform play. “When I was at Sony, the stated reason internally for this was money,” Smedley stated. "They didn’t like someone buying something on an Xbox and it being used on a PlayStation. Simple as that. Dumb reason, but there it is.”