This is definitely a huge improvement in the face of the last year's general election. It goes to show that even if people still didn't believe in a proper alternative to Erdoğan as a president, they are fed up with his party AKP's governing in their cities and towns.
More than 20 out of 81 provinces/states in Turkey changed hands this time, both in governors and city councils.
The main opposition party, secular and founding party of modern Turkey, CHP, has finally seen a very sharp rise in local governing popularity after not being able to win some cities for more than 50 years. It didn't lose any major city government or councils to right-wing AKP or other parties, although it lost a few smaller ones due to uncommon events, like electing to continue with the same controversial governor in earthquake stricken Hatay.
Another notable thing is that the Kurdish party has consolidated its local government in the mostly-Kurdish populated east provinces of the country. This has been the trend in the last few elections after AKP's popularity faded in the region, but Erdoğan decided to use his emergency powers he gained after 2016's controversial coup attempt to appoint his own party's nominees as governors instead. This election sees the elected Kurdish governors gaining their seats back.
One last notable thing to talk about how YRP, a rather more conservative, shariah law touting party, is growing in AKP-heavy central provinces. They had gained a few seats in the parliament last year, after forming a coalition with AKP.
As the article says, 2 local governors of the major cities, Ekrem İmamoğlu in Istanbul and Mansur Yavaş in the capital city Ankara, have won the elections once again in landslide vote differences (~10 and ~28 respectively). They both are and have been the main opposition CHP's candidates these last 2 local elections, and are seen as the primary candidates for the next presidential election in 2028, with the political atmosphere being unable to generate any popular candidates in AKP due to the shadow of Erdoğan looming heavy.