Thing is first, the Cantonese didn't exactly exist at the time large scale Chinese settlement began on Taiwan; second, the Cantonese didn't have much incentive to leave the Pearl River basin.
First, to clarify: Taiwan was not settled by the Hokkien. It would be more accurate to say that Taiwan was settled by both the Min-nan (the Hokkien plus the Teochew), and the Hakkas, both of which are from Eastern Guangdong Province and Southern Fujian Province. Taiwanese history often refers to the Hakkas as "Yue (Cantonese)", though this is kind of an error.
Min-nan in orange, Hakka in brown, Yue ("Cantonese") in Green. See how Min-nan and Hakkas dominate Taiwan.
Cantonese at the time was the prestige language of the gentry along the cities of the Pearl River Delta, more specifically the city of Guangzhou (or Canton, which is where the language gets its name). The precursors of the modern Cantonese people didn't speak Cantonese, but rather spoke mutually unintelligible
dialects of Cantonese--Punti, Taishan etc, most of which have been assimilated by the overarching Cantonese culture by today. Contrast that with the Hakka or the Min-nan, who were relatively united both linguistically and
had somewhat of a rivalry based on cultural lines.
Second, the Cantonese essentially sit on China's most arable land in the Pearl River Basin, and can easily expand further West into Guangxi if need be. The Min-nan sit on mediocre land, and the Hakka in unproductive highlands. This disparity attracted several waves of Hakka migrations into traditionally Cantonese areas. In fact, the Pearl River Basin was such good land that the Cantonese gentry thought that there was enough land to go around, and
welcomed Hakka immigrants into the Basin, who served as cheap tenant farmers (guest families if you will, the literal meaning of Hakka) for their Cantonese betters. Near what is today Hong Kong, where Hakka and Cantonese cultural borders meet, Cantonese village gentry (specifically the Punti) would often have subordinating Hakka villages, who then formed coalitions of villages to fight each other (
for extended reading). Eventually, the Cantonese sought to expel the
exploding Hakka population in the Pearl River Basin, and upon succeeding would solidify their dominance of the Pearl River Basin. Rather than emigration, the Cantonese are far more likely to face problems with
immigration.
To answer OP's question, I think a Cantonese Taiwan is extremely unlikely, even with an earlier settlement PoD. In fact, I think if China settled Taiwan earlier in its history there'd be
fewer Cantonese on the island. One plausible answer I could think of is for the Hakkas to adopt Cantonese cultural practices then move to Taiwan (perhaps a more united Cantonese cultural identity better assimilates the Hakkas?), or Ming China has bigger population problems, provoking overpopulation, conflict and emigration in the Pearl River Basin a century or so earlier.