I think it is possible to do that.. Just refer to the game archive of that specific player.. Then you will see the option says: 'download all games in one pgn', try it to see what will happen
Download Games For a specific player

Well it says
"Download All My Games in One PGN"
I have tried, but does not work for other players.
thank you for attempted solution

Common man it works and it is possible
I juts downloaded the first page of your games.
Follow the steps:
1- Go to the player's archive games whom you want to download his/her games,
2- From the Top Left side of the page choose the type the games you are looking for (live, turn-based, team matches, etc)
3- From the Top Right side of the page click on SELECT ALL, therefore you will see that ALL the games in PAGE 1 will be automatically selected.
4- Click on Download PGN file. The file will be sent to your e-mail
5- You need to repeat the same steps for every single page (let's say 500 games = 10 pages = 10 PGN files)
Good Luck

you have to click on select all first.
Still only selects the current page I believe.
How feasible do you think it would be to download all the games played by somebody other than yourself?
By paying for subscription, you have the option to
'download all games in one pgn'
this only downloads all of your games.
Would it be feasible to somehow download all the games, or rather most of the games played by a specific player with a game archive extending over 500 game?