Earlier quoted context omitted.
Being a customer shouldn’t protect a company from lawsuits. ARM feels they have merit here , just like Qualcomm did when they sued Apple. It’s not that rare in the corporate setting to have suits between companies with otherwise amicable relationships.
The optics can still be terrible. Qualcomm (or more accurately, Nuvia, the company they acquired) produced some stunning chips with almost unheard of battery life for a laptop, and Arm are suing them to use their own inferior designs. They even tried to have end user laptops recalled and destroyed! There's no world where this looks good for Arm.
And the fact that Qualcomm got just about everyone to endorse the acquisition ahead of announcing it but didn’t even tell Arm is a bit of a tell.