do you think the Bitcoin cap can't be raised if there's a need for it and users overwhelmingly approve? How is this even related to PoW vs PoS at all? in both system, the cap CAN be raised period
Within DPoS the delegates are also in control of the protocol itself. Within Bitcoin PoW the power dynamics are split between the miners, asic manufactures, users and nodes, and developers. Additionally, Bitcoin has a very large network effect where a critical mass has been created to introduce many competing interests and involvement unlike with many alts.
Within DPoS you have a mixture of the users/stakeholders and delegates/developers controlling the power with a very dangerous arrangement of only a few developers controlling most of the direction compared to Bitcoin.