When we had our tent trailer they were rather inexpensive and lightweight. Our first weighed only 1000lbs fully loaded. We pulled it with a small Suzuki Samurai which did great. Our 2nd tent trailer weighed 2000lbs fully loaded and was very roomy. Pulled it with ease with small Nissan truck (much smaller than todays Nissan/Toyota trucks).
Todays tent trailers are mostly high sided with all the bells and whistles, weigh considerably more and are priced close to what small hybrids or travel trailers cost.
I tend to think many feel at the weight and cost they might as well buy a hybrid or small trailer.