Totally depends what you are looking for, OP.
I am just back from a weekend there with my boyfriend (both late 40s).
Our objectives were:
- somewhere affordable to get away for a couple of nights - I am dealing with a bereavement and felt some distance would help.
- somewhere with lots of beach where his dog could go for a good run.
We found a lovely, pet-friendly apartment right on the sea front, for well under £100 a night. It had cooking facilities which we really wanted as we are both trying to eat more healthily.....
And the weekend was great, in that it offered us everything we wanted. Time on the beach with the dog. I spent some time shopping. (The town is decent, has most shops you would expect in a large town, and a decent range of charity shops too).
We had a little excursion on the tram, just to see a bit more of the place - the sea front tram is an affordable and pleasant way to see the sights.
To be fair, a lot of our time was spent in the apartment, watching films/reading etc.
We were smack bang in the middle of town, and weren't woken up at night by drunken revellers or anything. No idea if this would be different in summer. To be fair, we did consider going out to a pub, and were only prevented by our own laziness, not because we felt it would have been awful! But we aren't shrinking violets - I live in what would be considered by a lot of Mumsentterrs to be a "rough" neighbourhood, possibly. Not that there is anything especially "rough" about me I don't think - I am a normal professional woman in her 40s - but I don't know, maybe less bothered by things being a bit run down/shoddy than most?
Anyhow, based on this experience (first time I had stayed in Blackpool) I might take my teenage daughter for a couple of nights in the summer - I saw nothing to put me off!