TBH, even within my lifetime, Lahaina had been subject to a lot of new construction, outside the small historic district. It was a small town, by any standards, when the Europeans came. In 1850, Europeans came and declared a new land policy (stating that non-Hawaiians could own land). The rest is, well, history. It rapidly became a whaling town, but that was not acceptable to many local Hawaiians. The Kamehameha Dynasty was still technically ruling, but the history of Maui in that period is one of diminishing power and involvement from the Natives. It has been that way ever since.
The quirky little shops on Front Street were in a variety of wooden buildings, some of the larger ones were built in one month during the late 1800's.
Lahaina in 1831. This large structure (later demolished) took just one month to build.
Lahaina in 1854. About 200 people lived there, including a handful of Europeans (missionaries).
The New Lahaina Lighthouse .
Was built in 1905 (didn't take very long to build)
That was the year my great-grandmother and her parents left Maui for the Big Island, feeling encroached upon and wanting a more traditional place to live.
The historic district will certainly be rebuilt according to the standards of historic reconstruction - but the rest of Lahaina will be rebuilt, I believe, by the people who own the land on which things will be built.
The Kings and Queens of Hawai'i urged the building of the fort in order to keep out the whalers (and slavery/slave trade vessels were illegal in Hawai'i from 1852 onward. It would be really cool if they rebuilt the old school (from the 19th century) but the locals (via local government) recently decided to build a really nice, modern elementary school with all the bells and whistles to usher the children of Lahaina into the age of modern education. I would think parents and others would want that rebuilt. Typical school rebuild after a fire is about 2-3 years, but part of that is wrangling with state government, so maybe Hawai'i an make it happen sooner. They built a school near me on what used to be rocky, uneven soil and it took less than a year to complete.
It took about 3 years (from grading to opening) to build the new hospital (starting in 2016).
So...the questions will become, whose Hawai'i will be rebuilt? I have no clue who owns the Front Street buildings where the restaurants were, but I assume that the restaurants were leasing from someone. I don't think it's going to be a decade before Lahaina is liveable, but I do think it'll be hard to get enough workers and materials to get so many things done at once. Near the Thomas Fire burn scar (2017), about half the burned houses are still unbuilt - although most have their foundations and utility hook-ups installed. A few lots are completely empty. Almost 1100 structures were burned and 300 were damaged, approximately - most of them houses, though. I don't think any schools were burned.
So Lahaina's losses are huge. But Hawaiians are industrious and if they can get the wood and the concrete, they will rebuild as soon as someone figures out the next step (somehow getting all that charred rubble put somewhere else - I have no idea what they''ll do with all that).
Right now, it's the fearful thought that the death toll will rise that is the priority. The next couple of weeks are about searching, mourning and grieving.