Cama is Spanish for bed. A cama bus has seats that fully recline to form a flat bed. They are awesome. Semi-cama is a reclining chair. Not flat, but comfortable and you can easily sleep. And then you get regular buses, which are no fun on the long journeys.
"Leito" sounds more premium than "cama", despite being both valid words for "bed"
OTOH I had pretty good experiences with some Indian sleeper buses, if new/good condition, you can even choose single berth with solid sliding aisle wall making it your own small private cabin [2], though it seems aisle curtains are more popular, bed is completely flat, you can even pull open pretty big side window to observe country, though of course it's not long enouigh berth for 2m European, for obvious reasons double berth shared with strangers is not very good experience but sometimes there is no other option
so I wonder how actually look these cama buses you specifically mentioned
[1] https://warmcheaptrips.com/wp-content/uploads/2024/07/Sleepe...
[2] https://static.punemirror.com/full/276e634e-e89e-4231-b487-2...