eduadinho

Per the FA if a player impedes another player, pushes or holds them it's a direct free kick. Joelinton pushes Gabriel down and impedes his ability to play the ball.

Also if

HANDLING THE BALL

For the purposes of determining handball offences, the upper boundary of the arm is in line with the bottom of the armpit. Not every touch of a player’s hand/arm with the ball is an offence.

It is an offence if a player:

deliberately touches the ball with their hand/arm, for example moving the hand/arm towards the ball touches the ball with their hand/arm when it has made their body unnaturally bigger. A player is considered to have made their body unnaturally bigger when the position of their hand/arm is not a consequence of, or justifiable by, the player’s body movement for that specific situation. By having their hand/arm in such a position, the player takes a risk of their hand/arm being hit by the ball and being penalised.

Joelinton has made himself unnaturally bigger by sticking his arms out to push Gabriel. So it's both a foul and a handball

He literally threw his hands up straight after...

Gabriel is doing what you said. Joelinton pushing down on his neck and back stops him from doing so. Ergo it's a foul (also a handball)