While a Shinobi's dojutsu often tilted the scales for its user in Naruto, the same hasn't been the case for Boruto. The franchise formerly boasted the Three Great Dojutsu, namely Sharingan, Byakugan, and Rinnegan. Amongst them, the Rinnegan was reputed as the most exalted one. Nevertheless, the same dojutsu has lost its significance in Boruto.
As fans may remember, the only Rinnegan users in Boruto: Naruto Next Generations were Sasuke Uchiha and members of the Otsutsuki clan. While those characters have been pushed to the sidelines in Boruto: Two Blue Vortex, the manga has introduced four new Rinnegan users in the form of the Human God Trees.
Unfortunately, they have yet to utilize the dojutsu as well as their predecessors, losing all significance.
Disclaimer: This article contains spoilers from the Boruto manga.
The Rinnegan has lost its significance in Boruto

As fans may remember, when the Shinju first appeared in Boruto, they appeared terrifying. This was not just because they were mysterious beings clad in black but because they possessed the Rinnegan. As Rinnegan was reputed as the strongest dojutsu amongst the Three Great Dojutsu, it only made sense for fans to believe they were overpowered compared to the protagonist and his allies.
Unfortunately, from the looks of it, it seems like their Rinnegan are only for show. The Rinnegan is supposed to be the pinnacle of dojutsu that allows its users to use a variety of powerful unique jutsu. Nevertheless, the manga has shown only one Shinju (Jura) to use the dojutsu, that too, not to use any of its unique abilities but to launch a Tailed Beast Ball toward his enemies.

One can argue that Mamushi was using the Rinnegan to sense Eida when she was looking at the Shinju. However, the manga has yet to confirm this as the franchise has yet to disclose Rinnegan possessing such an ability.
Other than these two instances, there has been no hint of the Shinju having used the Rinnegan. This is quite saddening as the Rinnegan was previously reputed as one of the strongest dojutsu, with perception abilities greater than that of the Sharingan.

There is an argument that, as explained by Shikamaru, the Shinju were like Wild Beast Cubs. They not only lack combat experience but have also yet to train or make an attempt at mastering chakra control or their own powers.
Nevertheless, that shouldn't be the case for passive abilities such as greater perception. If the Shinju's Rinnegan were not for show, Hidari should have been able to outpace Sarada and evade her attacks when he was fighting her. However, it seems, the Shinju's Rinnegan are only for show. Thus, fans can only hope for the manga to show the Shinju slowly adapting to their dojutsu or explain why the Shinju's dojutsu were ineffective compared to the real deal.
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