I have a 5 1/2 year age gap between mine and don't regret it at all. Now nearly 14 and 8. They adore each other. The eldest does struggle with needing space from the youngest sometimes but other than that they are close. I think in some ways it's quite good for avoiding sibling rivalry that they are so different they don't expect to be treated exactly the same. They youngest knows he can't do everything the oldest does.
We do of course have to do things separately with them sometimes, but I disagree with pp who have said you can't find things they'll both enjoy. That's down to personalities of course, but they both enjoy theme parks, zoos, trampoline parks, beaches, board games, playing on the switch and just about find some films and TV they can both do. When they were younger there were stages where they enjoyed Lego or train sets together. Yes the eldest does end up doing a lot of the making up games for the youngest etc and needs time away from it but I think she enjoys the excuse to still 'play' sometimes because she's 'looking after her brother'.
It was much less stressful for me when he was little than chasing 2 toddlers around as well!
There are of course downsides - It is a bit harder to find things you all want to do occasionally, but I expect that happens with different personalities too. I suspect eldest gets less long walks / bike rides than age would if we weren't allowing for littler legs, but we can always take kids out separately if needed. We also find we don't have as many other families to hang out with where both kids will happily have someone to play with as those we know with 2 year gaps where sibling often in same class as siblings friends but to be honest we are pretty introverted so who knows if we'd have got friendly with those families anyway!
My mum has an 8 year gap with her brother and they are close as adults and I know she has said she is glad she has him, particularly now parents have gone. I certainly don't regret choosing a big gap over not having a second (which really was the choice, I found pregnancy and newborn stage far to hard to even consider doing it again with a toddler to look after, so it was big gap or nothing).