Almost all buses in the countryside are hail and ride. It might not be officially advertised as "hail and ride" but most of them work like that. On rural country lanes you can just put your arm out anywhere or tell the driver to drop you off anywhere. There must be hundreds of sections like this left.
This may be the situation in theory but it does not always work out like that. This all works very well on rural routes operated by a small local bus company with a small pool of local drivers who are on the routes regularly and know the routes and the passengers. It is not always the case when larger bus operators run routes through rural areas with a a big turnover of staff and drivers who are not local. There can be an attitude of “it’s more than my jobs worth“ to stop somewhere where there isn’t a bus stop sign.
Just a couple of examples I have witnessed.
A few years ago I travelling on a Stagecoach bus in the Castle Douglas area of Dumfries and Galloway. I wanted to visit Threave Gardens which is situated around 2 miles outside the town. There is a regular bus service along the road which passes the gates but no bus stop. I’d asked for Threave Gardens when I got on the bus and the driver wouldn’t stop at the gates because there was no bus stop there. Even though the bus passes the gates with a perfectly safe place to stop I was left with almost a mile to walk from nearest bus stop.
Another example and again Stagecoach. On my local route in Nottinghamshire there are a number of bus stops on rural parts of the bus which are for both directions. I have known drivers refuse to stop because it doesn’t say both directions on the bus stop sign, even though on the timetable displayed at the stop it says wait opposite. One driver tried to argue with an elderly person who had been using a stop for almost 40 years that he wasn‘t allowed to stop there because there isn’t a both ways sign on the bus stop. He told her that she needs to report it to the local authority.
When I am out walking in rural parts of the country I am always very cautious about relying on buses stopping where there isn’t a signed bus stop and usually try to start and finish my walk in the centre of villages where there is an official marked bus stop.