Re: Public utility should be provided by public entity.
Only someone who doesn't remember our old state owned/run services would say that. It's notable that when you see vox pop bits on the news about train fare increases - it's always young(ish) people calling for it to be re-nationalised.
So what did the nationalised Post Office give us ?
Well to start with, with very few exceptions you could only connect a phone that they approved and mostly rented to you. You had some choice, but not a lot.
If you wanted a new phone line, then they'd provide it, probably, eventually - typically the waiting list was months. And if they were running short of copper pairs, they wouldn't pull a new cable in to increase supply - they'd put you on a party line. For those who've never had the "joy" of a party line, you had to pick the phone up and listen to see if the other party was using the line - in our case, we shared a line with a couple of old spinsters a few doors up the street. If you heard voices, you apologised and put the phone down. If you heard nothing, you'd press a button (Earth Loop Recall) to activate the exchange and give you a dial tone.
And of course, in real terms, it cost a lot more than it does these days to have a phone.
Now, for the trains ...
Well we mostly had ancient dirty rolling stock, calling (if it ran at all) at dirty and run down stations, manned by (in many cases) DGAS staff who were both p'eed off with working conditions but also secure in the knowledge that it was hard for mangement to try and sack them - lest the unions walk out and bring the country to a halt.
The "passenger experience" could be summed up by the intro to this piece : https://www.campaignlive.co.uk/article/when-show-business-means-new-business/514715
That's not to say that privatisation has been 100% successful. But it made a huge difference to both telecomms and rail. Re-nationalisation would be a disaster.