But back to the OP's question...
Is buying a timeshare, resale or otherwise, ever a good idea? I'm not being sarcastic with this question but just really interested in your responses.
For some people, probably not. For many (maybe even most?), it can be a fabulous idea.
There are so many different ways to timeshare that they can fit almost any travel patterns, family situations, etc.
If you have a larger family (more than 4 people), timeshares are awesome because of the space. Most hotel rooms only accommodate 4.
If you want to travel economically, timeshares can be a great way to do that. The costs are usually in line with a low-end hotel (or at least they can be if you get the right ones), and the kitchens allow you to cook instead of eating out.
If you have family members with special dietary restrictions, you can cater to those needs by cooking meals instead of having to find restaurants that will work.
Some situations where buying a timeshare might not be a great idea...
If you don't vacation.
If you don't/can't plan ahead. While you can do last-minute stays with timeshares, it's usually better to plan ahead (6-24 months, typically). Not everyone can do that, and timeshares are far less useful/valuable if you can't plan ahead.
If you can't afford it. It's not just the upfront costs, but also the (ever increasing) annual maintenance fees, special assessments, and the cost of getting rid of it when/if it's no longer useful to you.
If you don't typically vacation a week (or multiple weeks) at a time, from Fri-Fri, Sat-Sat or Sun-Sun. Some systems do allow more flexibility in check-in days and stay lengths, but timeshares are still mainly weekly stays with Fri/Sat/Sun check-ins.
If you like to vacation primarily to urban areas. Many don't have timeshares, and most that do (like NYC) are more expensive and hard to get into. Timeshares are primarily in tourist areas.
If you like the pampering that comes with high-end hotels. That's just not how timeshares work.
If you're in poor health.
If your travel patterns, family, or life circumstances are changing drastically. While timesharing can work with different travel patterns, family situations, etc., what works best for one might not be the best for another. You'll want to figure out what works best for YOU, and if that's changing it might be best to wait until things are more stable.