Recently, Production Director, Cayo Braga, spoke with PC Gamer at GDC. He did not rule out that playable transport could be added to Arc Raiders in the future.
In response to a question about the possibility of a "quad bike" appearing in the game, he did not promise anything specific, but noted:
We have vehicle prototypes that were created seven years ago that we haven't touched in a long time — but, however, nothing is ruled out in the future.
The authors of Arc Raiders have big plans to support the project, so there is a chance that full-fledged transport will appear in the game:
We've been talking about [supporting Arc Raiders] for ten years. We want this game to live long. So, I think any options are possible — if they fit into our lore and the gaming experience we want to give gamers.