I had three until a couple of years ago. Then one, now two.
I would say it depends on the dogs. If they're three that can be walked together easily then it's not such a problem, but splitting walks and making sure everyone is properly trained and exercised can be quite a commitment time-wise.
We've never had problems with holidays because we usually go to a family owned holiday home and on the occasions we haven't we would kennel the more closely bonded pair (we've been using he same kennels for over 25 years and the dogs love it there) and take the other one with us.
I thought I would always have multiple dogs and was still thinking of adding a terrier into the mix a couple of years down the line, so that the younger one doesn't end up alone when we lose our older lad, but now we have these two, despite regularly falling for rescue dogs online, I really don't feel I could handle another. Thinking about it, we had three before we had our dcs and having a small house, three dcs (one of whom has SNs) and two dogs, the house is full - and chaotic enough. If the dcs had come first, I doubt we'd have gone for three dogs in the first place.
I should say though, that I have health issues at the moment, so that's probably colouring my point of view. Also, the younger of my two is particularly high needs, so that complicates things somewhat as well.
Dh won't walk both together either, so while I'm ill mine are getting less exercise than I'd like, because he has to split his available time for dog-walking between them.