I agree
According to a director of DB, he claims that it is correct that the universe is infinite and has no doubt to be questioned.
Another databook citing this
Link where it was mentioned:
another guide
宇宙のしくみ
Structure of the Universe
地球にとどまらず、宇宙のさまざまな星々を舞台に繰り広げられる孫悟空たちの大活劇。悟空たちが住んでいる「地球」は、DB世界では「北の銀河」に属しており、「4032の緑の877惑星」と表現することができる。
Not limited to the Earth, the stage of the big adventure of Son Goku and the others unfolds on various planets/stars of the Universe. "Earth" where Goku and others live belongs to "North Galaxy" in the DB world, It can be described as "4032-Green-877-Planet".
この世全体は球体をしており、さらに破壊神ビルスによって、この広大な宇宙そのものは全部で12あると言われ、悟空たちが冒険を繰り広げている宇宙は「第七宇宙」に属している、と伝えられた。
This entire world is spherical, furthermore, Beerus, the God of Destruction, said that there are 12 vast universes in total and that the universe in which Goku and his friends are having an adventure belongs to the "Seventh Universe".
*Note: The term "この世" can mean "This world" in contrast to "あの世" which means "other-world" as the land of the dead. So in the context of Dragon Ball, it might refer to just the world of the living. So when you see "This world" here, it might refer to "World of Living"
この世はどこまでも果てしない広がりを見せ、DB世界は人知を超えた途方もないスケールを持つ世界観であることがわかるだろう。
"This World" shows an endless expanse, you will find that the DB world holds a worldview with a tremendous scale beyond human understanding.
*Note: For anyone that is wondering, the term here is "果てしない広がり" which can literally mean "something that spreads out without an end"
この第七宇宙は、サイヤ人やフリーザ一味、魔導師ビビディが生み出した魔人ブウなどにより、何百もの星が破壊された過去を持つ。
In the Seventh Universe, the Saiya-jin and Frieza's army, and the Majin Buu brought forth by the mage Bibidi, destroyed hundreds of planets in the past.
また、悟空たちのふるさと・地球を含め、第七宇宙で起こるさまざまな出来事は、界王界の界王や界王神たちによって、中立的な立場で見守られ続けているのだ。
Also, including Goku and the other's hometowns, on Earth, the various events of the Seventh Universe are being continuously watched from a neutral standpoint by the Kaiō and Kaioshins Kaiōshin of the Kaiō World.
Translation credits:
guide name chozenshu 4 I think
Full quote from the guide