Great thread Dean!... and a wonderful opportunity to vent my spleen on a Sunday afternoon!..
With the rise of the internet do people still think they are as valid as before?
No.
Do people think they are a dying breed?
Yes.
Do they offer what people want?
No. Would you buy a fridge that cost £150 to make for £15,000?
Are some just not flexible enough for the customers?
It's not flexibility in my view. A global, internet-led market place makes high-margin high street dealers a dying breed. A plastic bag and a limited warranty isn't enough for me to pay thousands more..or many others.
Are they too opinionated or not opinionated enough?
High self opinion doesn't help in sales. I should know - I battle with it too

High opinions on this topic by the industry are sometimes a ''bury my head in the sand and pretend it's not happening'' type of response.
Customers shopping habits HAVE changed.. get used to it fellas!
Do they need to change a.s.a.p. to survive?
YES!.
If I was opening a hifi store it would:
1) Be out of town in a cheap location.. mostly a warehouse with a very small demo facility.
2) Run an internet store. Low margin, high volume, internet led sales.
3) Embrace products from the far-east, and run them along side traditional audiophile brands. I'd apply the same low-margin sales approach to all brands.
4) I'd embrace kit sales, and get kits built by local builders of both speakers and amplifiers. Low margin here too.
5) Make a marketing slogan out of ''why pay more?'' tesco's style!... After all... WHY PAY MORE?!!
Very strong opinions I know... but I strongly believe the average high street hifi shop has it ''dead wrong''.
Going back to my maketing at Uni days ''in a saturated market place diversify".
Another way to diverisfy is exemplified by the very best UK dealers. For example MAX, Walrus, Definitive Audio - diversification through extremely careful brand selection and best possible customer service. The BIG problem with this though - it's extremely hard to get right. Walrus, Definitive, MAX - there are only a few capable of it in my view - but many that try.
Traditional stores seem to go for the 'Definitive/max/walrus' model, but would be better going for the other model IMV..