Ireland’s monasteries were tremendously rich pickings for the Vikings. I’d be surprised if they wanted to expend the effort to occupy anything past the coasts and estuaries. In Britain their cousins the Jutes had made major settlements over the post-Roman centuries, as had their more distant cousins the Angles and Saxons. That hadn’t happened in Ireland. The area of East Anglia was quite low down, and the river estuaries were broader and reached further inland during the medieval warming period. Geographically they were of course closer. Another thing that went on in Ireland, which I don’t recall from British middle ages, was seagoing warfare between Viking chieftains. The intermarriage was pretty extensive, based on the first names and surnames, and marital alliances between petty Viking kings and petty Irish kings were commonplace. It’s not necessarily something the Irish crow about though. :’)
IIRC, there is a lot of Irish blood in Iceland. Apparently Ireland was a popular place for Vikings to “find” brides.