There are plenty of projects for which solderless breadboards are unsuitable, but there are also lots for which they're perfectly fine. Lots of hobbyists and most professionals will outgrow solderless breadboards sooner or later, but they're still a good place to get started.
Spend an hour in an undergrad EE lab helping people with fucked up breadboards and you change your mind rapidly. Same goes for hobbyists but they don’t have someone to help them available.
I’ve seen people chewed up for hours debugging a circuit and find it’s a breadboard problem.
Yeah, I wouldn't use them in that sort of setting.
I do use breadboards for quickly checking out relatively simple, low-frequency circuits. But if the circuit appears to be malfunctioning, I suspect the breadboard first (after double-checking the circuit wiring). I also think of breadboards as being consumables, and as soon as one gives the slightest whiff of trouble, I get rid of it.
I think they're very useful tools, but you need to be aware of how iffy they actually are and use them appropriately.
