If the universe in which there are no sentient beings will be destroyed, there would definitely be some value being lost. The value of beings is not defined by the sentient they have. The sentience is the same as other organs that make up a being and, at the same time, add one more ability to beings. So, whether a being has the sentience is the same as whether a being has wings. We as humans do not have wings like birds, but we still have intrinsic value as living beings. Different beings have different organs that provide different capabilities, but we won't use this as a criterion to measure the value of beings. Every universe which has different types of beings should have its own value- the value of existence.
One objection might argue that since those beings do not have sentience, they are unable to feel their value as living creatures, so even if they are destroyed, there will be no difference, in other words, there is nothing to lose.