As someone who's not religious, all I can say is that that religion can be useful by way of putting the fear of god into people. If someone is convinced that eternal punishment awaits for misdeeds and acts to avoid such deeds, it's not a bad thing per se. The problem thereby is less about how evil a deity might be (or how hypocritical a belief system may be), but how that fear is facilitated, not by any deity, but by the people that interprete what is right and wrong in the eyes of that belief.

Gods are one thing and I will not bore anyone with my personal opinion of any such existing, as simple as that opinion is, doubly so because that question is largely irrelevant because ever since any claimed direct contact and communication/creation of any such rules to follow, it has been not any form of deities that enforced such rules or altered them. It were people that have been using that fear to facilitate whatever it was they applied those dogma for. Prosecution of heretics, prolification of belief systems, extermination of competing belief systems or the more benevolent changes like scientific progress pioneered by scholarly monks which are often overlooked when discussing such topics as the question of the existence and their efforts to come to terms with their beliefs have led to many groundbreaking scientific, philosophical and moral advances.

Fear is a tool designed to deter as much as worship is a tool design to incentive and ultimately it all comes down on how it's utilized.

Whether any of that is considered cruelty is largely just a matter of perspective. One man's cruelty is another man's justice or whatnot. People are fickle like that, as are belief systems which essentially boil down to being reflections of human perspective upon certain questions (more often than not existentialism or morals, all of which are as faceted as are humans).