I built a whole computer (well, assembled a kit on a pc board) with an iron about that size when I was 13. It still works today, 36 years later.
I only acquired a proper temperature controlled soldering station in the past 8 or 9 years - and instantly wondered why I took so long to just buy the right tool. But I always made do with a collection of simple irons and a heavy duty gun for the really big stuff - 15 watt, 25watt, and 40 watt irons and a 200 watt gun. When I was a kid, we just had one iron about that size, 40 watts I think it was, plus a heavy gun. Somehow I managed to build the computer without delaminating the traces or melting any of the through whole passives. Thankfully EVERY chip is socketed so all I had to worry about was melting the plastic on a socket.
The toroid thing is a huge potential trap for younger players. Remember in one of the power supply teardowns Dave did, it appeared the manufacturer fell flat into the trap, but a close up shot revealed the insulating bushing that prevented solid metal contact between the bolt and the mounting bracket that otherwise would have cause the very issue mentioned. Even if mounted to a metal surface, there could be the same thing going on here - though from the pictures plus descriptions of the typical innards of pinball machines by others - I kind of think they more or less got lucky by not bolting it to a metal bracket.