I 100% agree, if you can sign up without a phone call, you should be able to cancel without one. However, at the end of the day, it's just a phone call. It gets a bit dramatic.
As a customer, guess what? I get it, it'll take longer to get my stuff. No big deal. It means a lot of people are being responsible, shopping online, and hopefully sending gifts rather than spreading COVID. Retailers should just not make shipping promises they can't keep, reasonable people will understand.