Everything you just listed outside of climing the 25ft latter (because I pay attention when doing electrical) and going into a 130 degree attic I've done.
If fix F* ups quite a bit, even in class because several particular classmates don't know wth they are doing, I'm usually fixing their screw ups.
Dealing with older homes, I've done enough of it as it is, I've even built a home from the very foundation to the complete structure. I have helped in the repair of 30-60 year old residential structures, and have aided in the repair and maintenance of 30-60 year old commercial structures. My entire training course is repairing and maintaining pre existing systems and structures, to include bringing them to code when required. It is not some BS HS garbage. I am not in High School, I am not in some BS goody boy school. I am in a Federal Funded Training Program and learn to do this kind of work.
In fact, of the crap you listed, I've done all of that but 2 items on your list, TO also add to crawling underneath a house flooded with 11 degree water from rain coming into the crawl space in the middle of november to pull pipes through the subfloor. To include digging 2ft wide 5 1/2 deep trenches to connect a house to its sewer main.
I have had to replace siding, caulking, remodeling an entire houses basement, and back home on break spending most of break fixing wannabe DIY Handymen work because they can't mentally comprehend the difference between a 2x4 and a 2x6 and can't mentally comprehend why you have to have the studs vertically level, and why you can't put 2x4s 24'' apart when its required to be 16 for 2x4s.
I've already dealt with and have had to fix enough wannabe handymen's crap. Thank you very much.
Regarding J,
It actually is true. At least in WASHINGTON, all houses built after ADA rulings, have to conform to ADA, to include counters, etc. etc. Same with Commercial Buildings even. The brand new bill and millenda gates foundation building? Everything in it is ADA complient, because it's a commercial building.
All Commercial Buildings have had to be reorgenized, modified, etc. to conform to ADA, newer buildings have to be build to ADA specs.
Regarding Tradesmen, they absolutely can make modifications on the spot if it needs to be done. In their case it's a phone call away, describe what's going on, 99 out of 100 times it'll be approved, they then go with it. And mark changes on the blue prints.
Engineers and Architects, deal largely with the shape/design of the structure. Individual Mechanical and Electrical systems, are outlined, which can be modified by a Licensed Electrician/Plumber/HVAC-R Tech as needed to conform to codes. They do not rush anything.
Project Supervisors and/or the General Foreman, can make changes on the fly, because they licensed to do it on the job site. They mark and list changes and modifications, and put them in notes for the blueprints, and then redraw the blueprints later to reflect the changes they made. SO long as the don't comprimise design/shape of the building and its structural integrity. I do not know how it is in your state, but in WA, they can, and do do this.