Gallant is tough but he is also known as a players coach. From what I hear, he is harder on management above him than on his players.
I do think Berube was tough on his team, but they lost their vet core, and they needed constant prodding. That is usually when the coach runs out of runway.
Seems like I see a lot of good former Blues are on other teams (we just saw Barbashev and Peiterangelo last night in Vegas, and we saw Perron and Fabrbri in Detroit last week). Their younger stars like Kyrou and Thomas are not yet at the leadership level of the vets they traded away. There ownership does not want to miss the playoff two years straight. They sent a message, changes are coming.
When you think about what the Sabres did with Eichel and Reinhart, you can really understand why their reputation around the league stinks. I also fear it does not happen again to the next group.
For the Sabres, I would be very happy if they interviewed Gallant and Berube and Brind'Amour, but I don't see it happening.