Take Jl. Semeru, for example. Right beneath the modern name, you’ll see the colonial-era "Smeroe Straat." The shift from "OE" to "U" isn't just an evolution; it’s a linguistic revolution.
The old spelling was based on the Van Ophuijsen system (1901), designed by the Dutch to standardize Malay using their own phonetic rules. But in 1947, the Soewandi System (also known as the Republican Spelling) was introduced to make the language more efficient and distinct from colonial influence.
I made a short video about it: From "OE" to "U"!