Fair; however, the trades are physically difficult work (I am also a qualified electrician and do plumbing work).
Ever spent any time trying to do plumbing in a house in the south with a crawl space? Pretty physically challenging work doing the ole duck walk while squatting down all day

.
Yes, it is good money, and good Lord knows we need more of them (if only to bring down the cost and the waiting line in many areas), but it is tough work.
I recently had my septic tank cleaned. A guy 68 years old who owns his own business came over and dug a huge hole (about 3 ft deep and several feet wide) to find the septic cover (Michigan doesn't require the tube access like some states). Man, I got sweaty just watching the poor guy work.
Same for car mechanics. It's some tough work breaking those ball joints lose!
As an engineer, I can keep working (or doing retirement work) as long as I remain sharp and can still operate CAD, schematic capture, layout, etc programs and write code in a few languages. I am pretty glad I don't have to do heavy labor (I am approaching my 60's) today (except when my wife makes me on our own house

).
Yes, there is good money in the trades, but man, it is some tough work sometimes. It can wear a body down.
I am a veteran of the USN and submarine service. My ex father in law once asked me if I had considered staying in as I could retire a young man (would have retired at 38).
I asked him:
1) How many men did you shower with today?
2) Have you ever seen anyone who retired from the USN sub service who still LOOKED young to you?
I guess what I am saying is that there is more to it than money to consider.