They will sink or swim. If they are old enough to apply to college, they are old enough to check their email. I don’t feel remotely sorry for any of them.
I told my kids this at the start of their college process. They mostly ignored me, unitl they couldn’t bear to listen to me badgering them anymore. My son, the youngest, did indeed miss an important email. He had to right the wrong by emailing an AO to ask in a groveling manner if an interview could be rescheduled. Good.
My daughter, now a senior in college, fully understands the importance of email. They do get used to it. But she also missed an important email back in the day. It was the one offering her admission from the waitlist to the college she now attends. But it sat unread in the inbox for three days before she read it. The ensuing speech from me was similar to this: “haven’t I told you 500 times that you check your email EVERY day!” It was probably colored with expletives and was also quite loudly delivered. Ha!