If you configure a product with a required assembly option and then go to the minicart, you can remove it. However, the same behavior doesn't occur at the checkout since it blocks the assembly options from being deleted.

Simulation

Add a product that has a required assembly option to the minicart and then try to delete it. You can test on the storecomponents https://storecomponents.myvtex.com/custom-bell/p?__bindingAddress=storecomponents.myvtex.com/

Workaround

N/A