Yes it is, you can check the email address that the email is sent from, which should be firstname.lastname@example.org.
We can also confirm that the text ,'what you can do with your BBC account' contains a link to click.e.bbcmail.co.uk. This will take you to a Using the BBC webpage explaining features available when signed in and using a BBC account.
If you’d like to keep your account active you can also sign in directly at bbc.co.uk/stay, rather than clicking the link in the email.
You can also see what the email looks like below:
I have been using my BBC account recently, why are you deleting it?
We have detected no activity on this account for quite some time. It may be possible that you're signed in with a different email address, or using someone else's account. You can check which email address is associated with your BBC account by visiting https://account.bbc.com/account/settings