It does, kinda. It's more accurately translated as 'to please', thus 'taithníonn sé liom' = 'It pleases me' or 'I like/enjoy it'.
If you know Spanish, it's a lot like the verb 'gustar' in that language.
Is the connotation here "They REALLY don't like it" or "They like it ok but not a lot"?
I would say it's a strongly understated dislike. That they dislike being so blunt, or so negative, but they pretty much can't stand whoever this is.
I am confused about word order. How do I know it's them not liking him instead of him not liking them? Would the other be, "Ni thaitnionn siad go mor leis"? Is the clue to the construction which pronoun gets the "le"? (please pardon the missing fadas)
Yes to both.
Well, that's what do I still seem to get wrong, likewise: to 'enjoy'= it is 'pleasing to me'= is 'reflexive' expressed in the 'passive form'. so the Subject is at the and.
Ní thaitníonn sé go mór leo is literally "Not pleases it greatly to/with them". Making it more like English it becomes "It does not please them greatly". This can be more loosely stated as "They do not like it very much".
The subject in the Irish sentence is sé (it).
Sé means "it", leo means with "them". Word for word, it does not please very much with them. =They do not like it very much.