I've done this many times, I know for a fact that almost NONE of the prep work, training, file organization, email handoffs, exit/handoff plans, and so on...were ever used except to allow somebody to make excuses on their 'delays' in the first few months after I left.

I've also worked in industries for many years, and was told this line about 'leaving on good terms'. Honestly though, you could just about nearly commit murder - your 'name' and 'reputation' don't matter if there money / a deal to be made. And you'll almost never meet ICs again, so why are you bothering to 'leaving on good terms'. Its a fantasy. Grab names and emails on the way out, though, might be handy.

And, sometimes, you should just go. Seriously. If you didn't care so much trying to make it all happen and work and 'meet timelines', all that would happen is something would fall behind and the management would finally do their job and give relief to the team you think you're helping by doing so much work to 'offramp' - and perhaps get the people they refused before because you were handling it. Seriously, just dropping your shit where you stand and walking out into the sun one fine day may be the greatest gift you give that 'team' of yours.