why DSLR cameras are still expensive?
 

And especially the prime lens. Some of these prime lens are more expensive than the DSLR itself. It's hard to move forward in other areas of photography where you need better lenses and accessories. Photography is an expensive hobby.

it is the electronics and some the glass

i have a 35 mm WORKHORSE of a Nikon F1 ( no battery needed 100PERCENT!!!!! mechanical )
-- never use anything other than a nikon snake chain strap - no razor can cut it

a very good FAST f1.1 72 mm lens was ( back in the 80's ) rather EXPENSIVE

and a 500 mm lens is still very expensive

grinding lenses up until fairly recently was COSTLY

Good lenses last - it's the body that gets replaced, so it's worth buying the best you can afford. But you get vendor lock-in. No good buying a Canon body if you have a bagful of Nikon lenses.
Keep an eye on third party lenses like Sigma, the ones I have are very good.

The guts for a camera in a phone may only cost $5. Millions upon millions produced.

A dedicated back for a high quality camera is still a huge complex device and unique to a limited market. That market is getting smaller by the day.

what area of photography are you're in now? And what kind of photography do you want to enter into?

I'm not into digital photography nor do I like taking pictures. My smartphone with an 8 megapixel is good enough for general purpose pictures.

Hi, SLR cameras were the bees knees at their time, as were medium format cameras, but time has moved on.

DSLR are a very small market these days, so are expensive, lenses are even more of a niche market, so cost that much more.

Nowadays, the bridge camera has replaced the SLR for most enthusiasts, whilst the compact has progressed beyond belief into a really useful tool.

My photography is done with a Lumix FZ45 (24x zoom) bridge camera & a Lumix DMC-S27 (10x zoom) compact nowadays, & viewed on a computer screen.

The principal cost of any camera system is: the lenses. And, that's also the reason for buying such a system in the first place.

I have Nikon cameras, both film and digital. They all are compatible with the same set of lenses, some of which are automatic and some of which are not. I have a few hundred bucks' worth of camera bodies, and thousands of dollars' worth of lenses ... and one lens, bought at K-Mart long ago, which is a miniature reflecting telescope!

It's the same principle that says, "if you're setting up a home stereo system, buy great speakers with most of your money, and the rest of the gear as an afterthought." The speakers produce the sound. The lens takes the picture. (The rest of the camera is just a light-tight box with a shutter.)

Another reason for an SLR is that the image-capture area is much larger. "Size matters."

To be fair though both last a long time

I had met a guy (fashion photographer) in Tokyo, who had ordered a lens from Nikon. (He was Belgian if that mattered to the story) He had to order it months in advance. Nikon couldn't even guarantee the finish date as they'd just tell him the process would cost x amount and be ready when it was ready. Seemed rather un-typical of any reply I ever heard of but it got finished when he was there with spec sheet in hand. At the time the process to get this glass was quite new and the demand for that lens may have only been a hundred or so.

Yes, lens cost quite a bit. There's a tremendous amount of quality assurance needed here though. When you pay for good lens - you get good lens. That matters when you're trying to get high quality photo's.
I don't have that kind of money and make do with my 18-55mm ones. However, if you protect them they'll last you a lifetime (so I am told)
I got my dslr cheap used though. Barely used and only $180 / $500.

There's a significant difference between auto cameras + smart phone cameras then any DSLR. They are actually quite impressive, but if you're looking for a great photo, you use a DSLR.