They installed spyware. That is more than enough reason to lose trust. IIRC, they did it more than once too[1].
If that isn’t cause enough, what is? Would it take pre-installed ransomware to lose trust?
https://thehackernews.com/2015/09/lenovo-laptop-virus.html?m...
I agree on principle, but Lenovo is no less trustworthy than any Smart TV manufacturer, such as Samsung, Sony, or LG.
It has become a common industry practice to subsidize consumer hardware with pre-installed spyware. The only solution here is to replace the pre-installed OS with an open-source alternative.
I would still pick Lenovo ThinkPad running Fedora Workstation over any iMac or Macbook product.