IMHO, perfect price discrimination is not usually a good thing. It's often discussed more in the context of monopolies. Under simple market models (e.g. no externalities, downward sloping demand curve etc.), a profit-maximising monopolist will set prices above the market clearing prince, resulting in dead-weight loss (market inefficiency).

However, there is one situation where monopolies achieve market-efficiency: when the monopolist can perfectly price-discriminate. This eliminates the dead-weight loss. But, crucially, this also means that all of the gains from trade accrue entirely to the monopolist, as consumers are all paying their own individual 'indifference' prices.

It's a value judgement, but I don't see this as a socially optimal outcome even if it is the market efficient one.