How to remove " 's" in a string?

Use

['’]s\b|[^[:alnum:][:blank:]@_]

See the regex demo.

Details

['’]s\b - ' or ’ and then s at the end of a word
| - or
[^[:alnum:][:blank:]@_] - any char but an alphanumeric, horizontal whitespace, @ or _ char

R demo:

> x <- c("@kyrieirving’s", "@jaytatum0")
> gsub("['’]s\\b|[^[:alnum:][:blank:]@_]", "",x)
[1] "@kyrieirving" "@jaytatum0"

follower.list = c("@kyrieirving’s", "@jaytatum0")
gsub("\\’s$",'',follower.list)

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