As you become successful in your field (or wherever), and further internalize the habits that are necessary to be successful, it's clear that many of these things are easy to do, it's just that people don't want to do them.
In other words ... it's obvious that many people don't want to be successful, and if they were to introspect deeply, they would see this clearly. In fact what they want is to be somewhere comfortable in the middle of the herd, not having to do too much work.
Most people want to be comfortable, not 'successful' in a way that requires ambition. But many people are brainwashed enough by the rhetoric of success that they don't realize it's not what they want.
There's also something I haven't figured out yet. Every time I give advice, I get a number of responses from people with self-defeating attitudes, explaining how this advice can't possibly apply to them because blah blah blah. These people build up belief structures that are obviously intended to keep them mired in their current situation, smelling of low self-esteem and defeatism. "Obviously" it's better not to be stuck in these belief structures, yet people will defend them vigorously, and in some cases fiercely. I don't yet fully understand why, except maybe that if someone believes there is a solution to their problem, then it must be their fault that they haven't solved it, and/or that there will be a clear failure that is their fault if they attempt to solve it.
Cause it may be obvious: lack of energy both mentally and physically (and by extension, lack of motivation and positivity). This seems to be a systemic problem of modern men (and women too, though at a base level women have more inherent positivity & survival skills IMO).
Put it this way - if you are lost in a cave (maybe a bad relationship, terrible job, difficult financial situation or combination thereof) and starved of nutrients (lack of exercise, bad diet, including maybe addiction to salt/carbs/sugar/caffine) you will have little energy to do what is required to find your way out.
God forbid dark paths, bad judgment, and bad luck has taken you even deeper. You may be approaching the point of no return - hopeless and without any chance of survival.
In this situation, it could be easier to simply curl up into fetal position and die.
I think unfortunately - when starved and depleted like this - that this is the option many will take.
Is it the fault of this starving, depleted individual that they should choose to die ? (is basically what you are pondering)
Some, perhaps many, people are past the point of no return - mentally, that is (most physical conditions easier to solve than mental). Choosing maybe not fetal position and death - but whatever substance or quick fixes they can use to ease the pain while they attempt to coast through the rest of whatever remains of their life with minimal effort or 'comfort' as you describe. This hopeless, self-defeating attitude a defense of their decision to go fetal and maybe protect that little area of the dark cave they choose to live and die now.
If we had to reach a conclusion or solution from this, maybe it too is obvious: eat healthy again, exercise; keep your body sustained and mind stable - for then it will be easier to climb out.
Alternatively - you might just get lucky, and someone may find and help you out of that dark place. Hopefully by allowing you to build the strength you need to get up and walk out on your own two feet. But we shouldn't necessarily reserve judgment on those who can't even get up. Who knows how long they've been down there, how many missteps were taken that got them to that point.