I disagree; Zelda games have always been a major draw for Nintendo audiences. Link to the Past was the best-selling game of 1991; Link's Awakening - released in 1993 on the Gameboy - was a defining game for Nintendo at the time and was directly responsible for a massive uptake in Gameboy sales (and was the best-selling game of the year.) OoT was an absolutely industry-defining success; it was the best-selling game of 1998, and it's the highest-rated video game of all time on Metacritic. Zelda games have always moved consoles and sold well; in terms of Nintendo's unit-movers, it's second only to Mario.

Of course the raw numbers look more impressive for BotW - there are 122m Switch units worldwide (and 30m BotW sales), but the N64 only shipped 33m units worldwide over its 8-year lifespan, and OoT still sold 7.6m copies (with another 6.4m on the 3DS).