It’s not supposed to be a primary browsing outlet nor a replacement for a VPN. It’s for specific use cases that need high protection. The tradeoff between speed and privacy for someone whistleblowing to a journalist, as an example, is completely reasonable.
Having too much bandwidth available to each participant would incentivize too much abuse. In my past experience, a Tor associated IP was already highly correlated with abuse (users trying to evade bans, create alternate accounts to break rules, and then of course the actual attacks on security).