(ETA: I see you edited your post to clarify — I will leave mine because there is significant nuance about the constituency)

Not really. Clacton itself certainly wasn't; it has its problems for sure but other seaside towns do, and the corner of Clacton that is closest to Brightlingsea is I think fairly well off?

The constituency also includes Frinton-on-Sea, which is really quite affluent as east coastal towns go and fairly affluent on a national scale — a whole bunch of properties over a million quid, and Walton-on-the-Naze, which is a nice place, a bit more modestly expensive than Clacton.

The constituency does include a place that is often considered the most deprived place in the UK — the coastal village of Jaywick which is essentially a holiday resort village that collapsed.

Quite a lot of the people of Jaywick resent the allegation, as it goes. It certainly is more functionally deprived than most places in the UK though, as you have a lot of people living in what were basically beach huts in a holiday park.

And you can be absolutely certain that Farage does not give a damn about Jaywick. His entire argument, essentially, is that he, being Nigel Farage and occasionally even being Nigel Farage in Clacton, is good for Jaywick because it raises Clacton's profile. Locals evidently do not think he has done a thing, and regeneration would be a council effort anyway.