I'd like to know whether these retail investors see Gamestop as artwork or as speculation/investment.

Artwork - they buy it not because of any intrinsic value or expectation of a dividend/capital gain, but because of reasons pertaining to subjective utility - childhood nostalgia, a desire to get symbolic revenge at hedge funds, entertainment value, or a desire to access gambling services in a country where online gambling is restricted.

Investment - expecting to make a profit through greater fool hypothesis, a short squeeze, or because they believe in the company (e.g positive reflexivity of stock price and exposure leading to more funding and business, respectively).

Arguably it's a combination of both, and I'd say it's a fairly new phenomenon in financial markets (not so much other markets), perhaps TSLA being another good example.