Hello, Vanessa! Thank you for the compliment! ❤️
I will start with stating that no travel ultracompact stroller is absolutely sturdy. These are the smallest pushchairs you can get so very sturdy is kind of out of the question. However, there certainly are quality strollers in this category as well, I will tell you which to look at.
First, the Babyzen Yoyo 2 is certainly that popular because of the quality. It's simple and thus well-built. So it's worth looking at for sure.
The Joolz Aer is also a very good ultra-compact that is worth getting in 2021. Spacious, well-built, but pricy and needing extra accessories that will mean even a higher price.
I was quite happy with the Chicco Goody as well, trying it out with a four years old... (read the full Chicco Goody/Goody Plus review here to know more).
Lastly, I will mention the Mamas&Papas Airo, Quinny LDN and Easywalker Jackey as good lightweight, travel buggies that are worth your attention.
Hope I helped! I wish you the best of strolls, stay safe!