[Samsung Galaxy S9+ Questions & Answers] scottusa2008:
It's more then just that, but in truth they can within a certain degree. While we may own the hardware, we don't own the software (will explain more in the other example you posted). Ownership of the firmware on the phone is by multiple parties since Google launched the Open Handset Alliance... So combined Google, Samsung, the cellular carrier and chipset manufacturers all have ownership of the firmware on your phone (respective to the modifications they make and so etc). The exception to this would be the core components of the android OS, those are open source if I recall correctly so people could make custom roms using that.

Carriers also set requirements on what can and can not be enabled. Also local/state laws may also play into this as well. So it's not necessarily because Google wants something enabled or not.

This is not a proper or fair example... Nor is it as simple as that, there is a whole mess of other things that factor into this.

First off your phone isn't considered an "as-is" item but one that dynamically changes with updates, new OS releases and etc. I have never seen a store that sells an android device that never changes, but rather they often (not all the time though) mention how it can improve or change with software updates. Mostly now a days it's common knowledge that an android phone will get updates. You would have known the device would receive updates and that said updates would include security updates, new features or even new android OS versions.

Second updates may also change functionality and sometimes (unfortunately) remove things too. As an example carriers, state/federal laws don't take into consideration what you want to use the phone for (i.e. download booster is available on T-mobile but is disabled on AT&T).

As an example call recording while helpful is not critical to the function of the phone. It's removal does not break the device nor does it cripple it. If they removed the dialer app and thus prevented you from making voice calls with the phone that would be a different matter. This would be more applicable to your example... Limiting the car's speed (which I will admit would stink royally) like this would be something they can do and since the car still moves under it's own power nothing was broken functionality wise... It's still a car and goes from point A to B, they just changed how fast it gets you there.

Please forgive the crude way this little example is put together, it's late for me and I work early in the morning... IMHO a more fitting car analogy would be along the lines of a smart car that drives itself on one firmware version didn't require a person to be sitting in the drivers seat. An update is pushed to the car that changes how the auto-drive works and now for the car to drive itself someone must be sitting in the drivers seat at all times while the auto-drive is enabled. In this auto-drive example the removal of call recording during a phone call is the same as removal of the drivers seat being empty when auto-drive is enabled.

Third while you may own the hardware, you don't own the software in the car. This is the same principle that applies to computer purchases with windows installed on them, Xbox One, PS4, LG smart TV's, Smart Washers, etc. In this case we are granted a license to use the software, but being granted a license to use the software and ownership of said software are not the same thing.

Again please understand the example you used is far more involved then as you wrote it, and there is more to consider then what I wrote as a response. In the same token don't take what I say to diminish nor dismiss the value of what your saying, but rather there is more to it then what you may think.

Nevertheless unlike a car you do have other options to achieve what you want.. In particular there are 3rd party SMS clients that do offer the ability to export text messages. I used to use GO SMS pro for that feature, but there are other ones I am sure that do the same thing. Using an Exchange account I can get text messages from my phone as an email, so there is another method for preserving conversations also. For call recording I use a personal PBX server, but other dialer app alternatives exist that offer call recording so you might have luck with those too.