This sounds like a business is just something that happens to fall on your lap while you're fixing a pipe rather than something that you build with your blood sweat and tears. Most tradespeople make nowhere close to 300k. Their success is credited to their hard work, not their happening to choose the trades.
One is being the trades is rewarding, yes not all bring in 300K+, but I don't know a single trades person, many often my junior, who don't bring in a good income pretty comparable to software engineers at non FAANG companies make (typically 150K+) and I don't think any of them are carrying high debt student loans (many states even pay for trade education outright) and their benefits can't be beat, esp. if they're union.
The second is that there are trade businesses that do earn, esp. right now in the industrial sector, but they all have a singular thing in common: Travel Travel Travel. thats the name of the game. They're gone alot. For instance, my cousin is an industrial electrician, and works on windmills. He travels all over the midwest and Texas to do the work, is rewarded quite handsomely for the privilege, but is gone over half the year. Has no wife or kids currently, so there is that, but its taxing. Other trades folks I know have businesses and do pull in alot, but the "grind" can be very real at times, but I've been told that its rewarding, because its yours at the end of the day
Third is in a specialized sliver of robotics / industrial systems, you can make a fortune, but its not so outsized across the board. Medical systems are a big one, robotics are being really big in surgeries, and there's alot of money to be made there