To be fair, the GUI was purposefully eschewed to instead focus on shoring up the Cryptonote codebase (which, frankly, they've done a fantastic job on. The Monero daemon and blockchain are some of the most stable and battle-hardened in crypto). Past speed of development aside, there's been an explosion of interest in Monero, and the development community has seen a number of new and eager contributors. I'm not sure the prior development during a period of extremely atrophied interest is any indication of what development will be like moving forward.