The liquidity pool is one of the core technologies behind the current DeFi technology stack. They make it possible to diversify transactions, loans, income generation, etc. These smart contracts power almost every part of DeFi, and will likely continue to do so.
Even in the case of large size, it will lead to extremely low slip. In fact, the spread on Curve can compete meaningfully with some of the most liquid centralized exchanges and OTC service desks.