I believe so, Cowboys are one of the most hated teams in the NFL. Fans of other teams don't like the spotlight the Cowboys get. So, they enjoy seeing the Cowboys lose, more than they would enjoy seeing other Non-rival teams to their favorite team lose. Criticism might be deserved in some aspects. But, I for sure feel like some look forward to seeing Cowboys players fail at certain goals, so they can gloat about the Cowboys losing or failing to win playoff games in over 20 years.
Being a QB of the Cowboys just brings a brighter spotlight than being a QB of a franchise with less history, IMO. Dak is one of the most criticized QBs, even though there are QBs starting, who has failed to get their team into the playoffs. Matt Ryan and the Falcons are hyped up to be a playoff team every year, yet I don't see shots taken a Matt Ryan, as much as they are taken at Dak. Dak gets constantly put down and called trash.
Stafford, another QB that is praised to be great, has failed to make the Lions a consistent playoff team. Not criticized as much as Dak if for needing a certain supporting cast around him, to take his team to the playoffs.
QBs that were drafted higher than Dak and have been in the NFL longer than Dak, with no Superbowls or many playoff appearances, don't get as much bashing or criticism that Dak gets.