I suppose that when the chairman of the Barbel society states in print that he always fishes straight through with 20lb braid and is happy that the hook, (or the fishes lip) is the weakest part of of his set up then we can be forgiven for thinking that "barbel fishing has changed". Fortunately this is not the normal way of fishing, at least not among people I choose to fish with but I believe if we were all to follow that example we would be on a slippery slope and in danger of moving away from being anglers and entering the world of the trapper.
I'm not saying I've never used those tactics myself when fishing in snaggy areas on smaller rivers but tbh I was never happy doing it and at present I don't even own a spool of 20lb braid.
That's not to say I don't use heavy lines, one of the venues I fish on the Trent is full is sharp rocks and to give myself the best chance of landing anything I hook I have started using some 18lb line which is sold as sea line, it's main advantages are that it's cheap thick and abrasion resistant. I start off with a measured 100 yards tied onto the backing line then simply strip off any which gets damaged during the day, at the end of the day or before the next session I replace everything back to the knot.
Another place I fish on the lower Severn has mud/silt banks and little or no weed or snags, the classic 'clean bottom' I tend to use a 1.5 lb tc rod here and match it with 8lb mainline, I use a 3.2lb bottom there and target the bream, confident that should a barbel move in I can land it easily, I can't recall ever loosing a fish there on that set up.
I don't just fish larger rivers, I also fish the Teme and the Dove, where I normally use the standard 10lb mainline and 1.75 rod approach. Rigs are dictated by the swim and the river conditions, I tend to make mine on the bank and carry a large selection of hooks, too many really but I always have a few to hand out to anyone who seems to be struggling, I like to have the flexibility to be able to change methods if the one I'm using is not working and like to think you can learn something from everyone you see or everything you read, sometimes what you learn is how not to do a thing. Some of the most valuable lessons I have ever learned have come from watching some of the match anglers fishing the big open matches on the middle Severn in the 80's, Dave Harrel must have thought I was stalking him at one point but What I learned about feeder fishing from watching him for a few hours would have taken me years of trial and error, for instance, would it occur to you that you don't always have to fill the feeder?
There is much to be learned from the 'old school' way of doing things, I am slowly building a half decent library of old books and have been surprised to learn that much of the stuff we look upon as new and cutting edge is nothing of the sort and simply a rehash of something which was being done 100 years ago, they do say there is nothing new in fishing but there is plenty to be rediscovered. In conclusion I would suggest that barbel fishing like all things is actually in a constant state of flux, the recent move towards heavy rods and lines has been driven in part by fashion and in part by a vociferous minority of anglers who have found a couple of swims where the old bait and wait works well and provides them with a constant string of doubles to post on their blogs and sell to various mags. I'm not knocking it, if you are happy to feed a swim all day and then fish it for the last couple of hours and you can make it work for you then that's your prerogative, but to use a golfing phrase, "don't let it be the only club in your bag".