Such positive results for continuing online services after Covid were unexpected, but as the pandemic’s longterm effects on day-to-day life are still unknown, perhaps this is not surprising.
However, it’s worth noting that while online services means seniors and others shielding can access church, they also provide a way for others to choose service-on-the-sofa over physically meeting with church family. There may be a risk that pre-Covid expectations about attending church on Sundays (i.e. getting dressed, leaving the house, travelling to church, talking to church family) have now become optional extras.
Church should not driven by numbers, but they are a useful indicator of individual church health. So it would be a tragedy if churches, especially those that have grown during Covid (see below), now saw participation and engagement beginning to decline.