No, it doesn't affect game developer hobbyists (actually, if anything, it makes them more secure, since Unreal would have a broader pool of paying clients and less beed to squeeze low-revenie games before they can afford it.)

Unless you mean, e.g., movie-making hobbyists where they go from never having to pay to having some (probably, as currently exists for games, based on a revenue threshold) some condition where they would have to pay, which might drive some of them to a different toolchain, though if it is setup similar to gaming, it won't affect most hobbyists unless they have way unexpected success, so probably shouldn't rationally affect hobbyiat choices much.