Simple reason: SSD are more expensive than HDDs per Gb at the moment.
Simple solution: fit a 1TB SSD - might cost you a ton but well work it. And whilst you are at it put as much RAM in the thing as it can handle - 16Gb minimum - which will speed things up.
Simples?
Another for SSD. I have a Windows desktop ‘all in one’ 23inch touch screen. Which is nearly 9 years old. Ancient in IT terms. It went dreadfully slow. About 2 years ago I put a second drive in which was made the primary drive. It’s an SSD. Only 240 gb. But it does all the work. It boosted the boot up and usability speed massively. It will now continue to serve my purposes for a few more years to come.
I would not make a new purchase without an SSD boot disc. SSD’s have come down a lot in price lately.
Also having iPads and iPhones I will wholeheartedly agree that the compatibility issues are a pain in the butt. Mostly down to Apples intransigence. But they are nice and an Apple desktop would compliment my set up, but, like Buckman, find they are too expensive.
Incompatibility example: Someone earlier mentioned Amazon Prime cloud free photo storage. It‘s good, and a better interface than Apples I think. However. When linked to an Apple device. All videos get automatically uploaded and there is only limited storage for them. This is because Apple store videos in the same folder as pictures. If anyone knows a work around I would be interested.
John