The issue is those that want an easy introduction to Mastodon are the least likely to hazard a migration to another server later. Hence we are looking at creating a monster instance that dominates the Fediverse.
Random allocation to, say, one of 10 trusted instances would, imho, make better sense.
Not to mention that a monster instance moves us towards a single point of failure.
I would have hoped Eugen would have trusted others to offer at least an equivalent service and grow them as equals. I worry that out of the blue annoucements invites unhelpful criticism and division. Perhaps as Mastodon matures a move to a more consensual approach would avoid this.