Are you under the impression old people don’t go to church? Have you been to a church service?
On Easter Sunday, churches are full to the point where they have multiple services throughout the day to accommodate everybody. So, while possible, it’s not reasonable to hold an Easter Sunday church service in these times.
And potentially my family, if you decide to cough on my groceries after the service. since you think it's safe to shop, congregate in large groups, etc.