I'm not sure there's as much to worry about here as you might think. For one thing, Festool keeps its tool designs for a long time. Many of the tools you can buy today have been available in the same basic form for a decade or more, with only minor tweaks for usability improvements every few years. Given that Festool's warranty is so broad, this suggests that they're overall fairly confident about the durability of what they're selling: if things were falling apart, it would be a much bigger problem for them than the customers and would likely prompt design changes. (And despite what a lot of people seem to think, it's actually pretty hard to plan obsolescence into devices with widely-varying usage patterns such that they will predictably fail after their warranty expires but not before.)
The other big factors are that because that warranty is so broad, and covers wear-and-tear during the first three years of ownership, people will be more inclined to send tools in for service or replacement for relatively trivial issues resulting from hard usage that they likely wouldn't have bothered with if they had to pay for it themselves. Combined with their turnaround time guarantees, this is going to result in some number of tools that will be replaced rather than repaired, leaving the old tool to be reconditioned and resold. The no-questions-asked 30 day return policy also likely contributes to a number of tools being "borrowed" from dealers and then returned with light usage for a full refund. (I would especially expect this with more specialized tools that people need infrequently.)
The last thing I would note is that the Recon site doesn't seem to go through all that many units in the average day. We're talking dozens at most in a highly active day, likely, based on how long they last and how many people we know are buying them just from posts here on the FOG. We notice them all because we're a bunch of crazy fanboys paying close attention, but in the grand scheme of things, for a company that does north of $400m USD in sales every year, this is barely a rounding error.
My gut guess would be that the higher volume of Recon tools relative to the past is largely an artifact of the brand being much better-known than it used to be, and the number of people picking up hobby woodworking having spiked due to the pandemic.