See, I have a magic system and most people can practice a decent amount of power. There are two primary kinds of mage. Sorcerers can give their mana different properties (like making it sticky, solid, etc.) and convert their mana directly into various forms energy, but lack the ability to completely manipulate external forces. Wizards use spells for specific magical effects, like sending out a concussive wave. Prophets/PHEts (People of the Higher Entities) are uncommon people who can perform powerful miracles (like curing cancer) and/or curses (like causing a generation's first-born to always become a serial killer), but must be chosen by this higher being. One could also make a contract with a magical being, like a fairy or demon, to share their magic power. Depending on the contract and strength of the creature, they usually can outperform most average and skilled mages. The most rare magic practitioners are called Magi. There are Magicians who can practice both sorcery and wizardry (and sometimes even miracles and curses), Warlocks who have a formidable innate talent (like controlling the weather), Chains who can bind other living creatures to their will, and Chaotics who can affect probability and change the balance of entropy and use hexes to cause good or bad luck. Arcs are those who wield ancient forms of magic, similar to modern sorcery and wizardry but blurring the lines between them and possess various unique attributes (like fusing with nature or local space/time/spacetime distortion).
I imagine magic primarily being done small-scale, like affecting what's in one's line of sight, speeding up or easing mundane tasks, etc. Large magical feats like conjuring/destroying a building require many people and extra magical fuel, or an exceedingly powerful Magus. However, magic cannot be automated and every magic sequence or spell requires an active casting.
However, I still want a society based on technology and focused on advancing technology, either modern day or 20 Minutes in the Future.. For what reasons could technological advancement (and its motivation) be resistant to magic?