There are practically limitless opportunities to make things that people want. When we invent a machine to do work, the people freed from that work are available to do other work. So humanity can now make more of the things we want.
Imagine a list of tasks, each of which involves making something that humans want (now or in the future). The list is arranged in descending order of necessity, so things at the top of the list are the ones most necessary to human life. The list starts perhaps with collecting water, growing corn, etc and heads off past providing space travel at giveaway and away into the barely imaginable. Making flat screen TVs for most houses was once a task way off in the unimaginable. I don’t think we will ever get to the end of the list.
Imagine the human population as a team at a row of workstations arranged in the order of the task list. At the start of human history, the whole team was working on the first few tasks at the top of the list. Most of the workstations were empty, corresponding to the tasks not yet of high enough priority to earn a human. As technology developed, some human time became available to put into next thing on the list. In other words, as a machine became available that could replace the labour of one or more people, the human “team” shuffled up the row of workstations, so the next empty workstation became a manned workstation. The people displaced by the machine may be shuffled in to the team lower or higher along the row of workstations, but there is definitely a workstation available for them, so long as there are tasks stretching beyond the line of workstations. Humanity as a whole has more goods by everyone working than if any single person has no workstation.
If you accept the proposition, you also realise that the only reason we have unemployment is that guards are standing around stopping people getting to workstations. The guards are rules and other measures deployed by the government.