Perhaps Tyvek would work for a tent/tarp in arid conditions but I would hesitate to use it outside of summer or in wet environments. Especially without a rainfly. Tyvek is not waterproof and a good soaking or standing water under it will come right through.

Even through hikers who look for the lightest material possible to carry for 1,000's of miles do not use Tyvek as much as sil-nylon type materials. And even then its usually a single season/trip usage.