You are right, things have changed, and not for the better.
To address your comments:

• The local hobby shops have been gradually going under. As internet sales increases, the LHS couldn't match the prices and had to close
• Clubs have been closing down due to losing their flying fields, lack of members or outside issues forcing the matter
• The largest online retailer, Tower Hobbies, had its parent company go bankrupt. The company that bought what was left dropped several brands, Top Flight and Aquacraft being two that come to mind
• The manufacturers that are left are catering to the "I WANT IT NOW!!!!!" crowd. Almost everything being sold now is a foam or ARF that is made in Asia.
• Electric has become the power of choice since it's quiet and doesn't require any "tinkering", not to mention it's cleaner since you don't have to wipe "slime" off of your plane. With that said, YES, nitro and gas engines are still available. You can still order OS, Evolution and DLE engines through Tower, Dessert Aircraft and BH Hanson are still around so yes, you can still fly fuel powered planes
• Yes, kits are hard to find but are still available. Sig has changed hands but is still in business, for starters. Balsa USA is also still around, if you're looking for larger or more complex builds. There are also several private "kit cutters" that are laser cutting kits for planes that are no longer sold or made by manufacturers that have gone out of business. Then again, there's also the option of building from plans. There are several places to buy or download plans from that you could get printed out.

Yes, the hobby has changed but it's not dead. You have to look a little more to find what you need and preplan more than you used to but it's still viable. The biggest things are to not get discouraged and to do what you used to do:
HAVE FUN AND ENJOY THE HOBBY!!!!!
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