I never realized there were actual names for this.
I'm not so sure that it really is where I am right now. We've suffered from poor management decisions for a decade: Inadequate cross-training; refusal to hire staff with my level of technical capability. As a result, the company cannot legitimately hope to support a hundred corporate customers without me. Also, they've categorically refused to spend any money on professional development of staff - so our skills are now pretty consistently ten years out-of-date - so as much as we're trapped by how old our skills have gotten, they're trapped by how old our technology is. No one would really want to come work here, anymore, especially once they get wind of how poorly the company has addressed professional development, and how the company has failed to increase salaries above 2001 levels.
Regardless, it would take someone suitably qualified three years of working side-by-side with me for that person to be able to replace me, but of course, if they're going to do that, then why bother? Then they'll be dependent on that person, saving what? $10k? $20k maybe? The cost of doing that, at this point, exceeds the value of replacing me. And replacing me with two less expensive staffers would take even longer to accomplish, kicking that can even further down the road, and wouldn't save any money until their more up-to-date skills come into play. That's pretty far down the road, from where we are now.
And even if they do decide to do something, along either of these lines, it'll probably take them from one to three years to make that decision. I figure that I'm relatively "safe" for perhaps up to six years.
And I don't actually have any reason to think that my safety in that regard is in question, in the first place. I'm not actually stepping back so much as asserting myself in terms of forcing management to make better decisions from now on. No longer will I just take assignments that reasonably require different (or more up-to-date) skills from those we have on staff. I am now doggedly adhering to rational staffing expectations, and pushing any gaps back onto management as their failing (in clear, albeit more polite, terms). No longer will I let them fall back on, "Any engineer can do any engineering" idiocy, but rather say, "Yes, we can do that - I'll put out a req for the six new people we'll need to have on staff to do it." (I think it is very important to start a "no" with the word "Yes".)
The end result of my reasonable pushing-back is less work for us to do, i.e., more of my time is spent waiting for QA to find bugs for me to fix, rather than bouncing back and forth all week between bug fixing and new development. It seems like "coasting" to me.