Wait for More Details
The videos we've seen will help you set expectations as we push closer to the game's release. That said, loads of details are still missing.
We don't know if there will be DLC, something that would add replay value to a game where the single-player is the primary component. We also don't know if there will be a playable demo or a beta.
Answers to those questions might come in early 2020 or they might not. The game is still in development and it could be weeks before the developer puts everything out on the table.
If you're unsure about The Last of Us Part 2, either because of gameplay or money concerns, you might want to wait until we know a little more.