This is why you always book it as one flight with the airline even if it has multiple hops - its their responsibility to reschedule all the missed connections for free.
There are advantages to having your own domain - you can use something like [email protected] so each site you sign up to gets their own unique “to” address, that way you can easily send their mail to trash when you dont’ need to deal with them anymore, and will also let you know what company had a data breach if that unique email address starts to get spam.