Yeah, for me it's fishing or hunting...requiring a total disengagement from technology and (most) people.
Beaches are fun, but I wouldn't consider them a truly contemplative vacation unless it's some super expensive, exclusive, far away place...and like you said that's not for everyone.
However, the longer vacation is good advice. When I was severely burned out at a previous job (start-up) I was eventually fired because I couldn't continue the 70 hours a week and have the same, high output as I originally did when I started (I was averaging 70 hours a week for almost two years in addition to a long commute time and this is after working with the same people at a job before that where I was working about the same 70 hours for almost 3 years where I was also expected to have high output).
When that happened I ended up having roughly 3 months off of work. Joined a new company and it was amazing. My burn-out, which plagued me for years and caused an anxiety attack so strong I thought I was going to die of a heart attack (very severe chest pain; tried explaining to my 2 year old what to do if "daddy passes out") to feel essentially dissolved.
Burn out isn't fixed within your typical vacation period at a job. Most of my friends who have been, or are still, burned out have never had it go away until after taking months of time off.
First, physically resting and getting outdoors in the summer months can certainly just help you rebalance enough to make good decisions. You might realize that very short-term problems are weighing more heavily on you than you realize.
Second, it's a test of how indispensable you are at work, and forces other people to try to do things before asking you. You'll learn which things you need to make sure to train them to take over when you leave, and they'll remember the answers and approaches better if they have to figure them out themselves.
I guess it's possible that two weeks would cause irreparable damage... I have no idea what you should do in that case. I can't say I'd stick with it in that scenario, that's a horrible trap to get stuck in especially if you can't imagine it getting better.
Essentially what I was getting at was: a short vacation isn't going to do anything. If he can make it so he can take a very long vacation then that means he either transitioned enough so others can run it for him or he quit. Either way sounded like it would work out for him at least which is what I was aiming for with my comment.
In most cases, the anxiety and stress from a work environment didn't happen overnight, and it's not going to go away overnight.
I do think most people don't quite get that until they're in the thick of it. Seen it with more than a couple of friends, and in every case, the only option was to walk away and switch work situations. If it's causing you that much stress, there's almost never a great reason to go back vs getting something new.
But taking a break from the stressor, and/or delegating some of the work and stress, yes.
IMHO
[0] https://www.amazon.com/E-Myth-Revisited-Small-Businesses-Abo...