Is there Animosity Between 49ers WR Brandon Aiyuk and Kyle Shanahan?

The messy contract negotiations between Brandon Aiyuk and the 49ers may be just business. Aiyuk wants $30 million per season and the 49ers are offering $26 million per season and they're taking their time to compromise.
Or these negotiations may be personal.
Remember, Brandon Aiyuk has taken a backseat on the 49ers for years. Kyle Shanahan put him in the doghouse for the first half of 2021 and insinuated that Aiyuk was unprofessional. Since then, their relationship has seemed frosty at best. Now Aiyuk has an opportunity to force Shanahan to acknowledge how important Aiyuk is to the offense. And Shanahan has an opportunity to dig in and show Aiyuk that he's replaceable.
Two years ago when Deebo Samuel requested a trade, reporters asked Shanahan why he's confident the team could work out an extension with the disgruntled wide receiver. "We have a great relationship with Deebo," Shanahan said. "I haven’t seen him a lot since the season ended. I think it’s a little bit easier when you’re dealing with people without screens and phones in front of you."
Shanahan was able to work things out with Samuel because those two are friends. They genuinely like each other.
Shanahan and Aiyuk are not friends. They're colleagues. And it seems that Aiyuk resents the fact that Shanahan doesn't think higher of him. It was reported that the 49ers tried to trade for Justin Jefferson this offseason, which shows that Shanahan thinks Aiyuk is a tier below the top wide receivers in the NFL.
It will be so interesting to see how this standoff resolves itself.