No longer have access to email for my XBOX account

Check this info for compromised accounts:

support.xbox.com/my-account/security/compromised-account-solution

Otherwise contact xbox support account section to solve this issue

support.xbox.com/contact-us

Quick answer is Yes it will.

The only thing that it is doing is adding the new email to the account and making that email the email used to sign into the account. All purchases and everything go with the account itself.

Microsoft does this because they know people change emails and sometimes no longer have access to those email accounts like if they use the ISP for their email and no longer have that ISP they would no longer have access to that email address.

I have the same problem. The email on my xbox live account is years old, I have no access to it anymore, and I am unable to add a new email because "I still need to verify my email." That's pretty difficult considering I no longer have access to it. Great
system xbox

The problem is that it was linked to an email i no longer have access to. i cant get into the account thats linked to my xbox account. I need to unlink it without getting into my EA account.

if they are Microsoft email addresses then they are permanently linked to the Xbox account.

if you add an alias email then remove the Microsoft email address it will delete the Microsoft email account and you will no longer be able to access anything else connected to it, such as Office 365, and you will no longer be able to send or receive emails
on that account