I think that most of the problems people who don't really know D&D are having with this game have to do with the fact that all characters are starting at Level 1. Level 1 D&D characters are babies. They are weaklings with very limited abilities. When you are used to playing other video games where spellcasters are endlessly spamming spells, a Level 1 mage in D&D will seem like they can't do a God Blessed thing.
D&D has always been about balancing classes. The mage class isn't supposed to be an Emperor Palpatine Unlimited Power Blasting Everyone With Force Lightning Constantly class. You aren't supposed to go around hurling spells everywhere all the time. That's overpowered. Honestly, if they were going to do that, they'd have to REALLY dumb down the mage's spells' effectiveness. Fire Bolt, for example, would have to do like 1d4 points of damage or something. Magic Missiles would need to do like 1 HP of damage since they can hit every time, or they'd have to make it so Magic Missiles don't just hit every time, which is one of the most important benefits of Magic Missiles.
I don't get why so many people say that D&D doesn't work with video games/ CRPGs. It is no different for tabletop as it is for CRPGs. Whether I have limited Spell Slots in Tabletop or CRPG, the concept is the same. The point of the Spell Slot limitations is to make sure the mage isn't some all powerful, overpowering member of the team. You save your spells and use them strategically and wisely. It's about strategy, not spamming spells. That's the point. Think of Gandalf in the Lord of the Rings. He didn't go around blasting everything all the time with magic. A lot of times he fought with sword and staff. He saved his spells for when he really needed to use them.
As it is, in all other versions of D&D, Cantrips were also given limited spell slots. In 5e, they finally made Cantrips so that mage's could just use them endlessly. I like this. It does allow mages to at least use some sort of spells regularly, even if they are weaker. I also think it works well that as they increase levels their Cantrips become more powerful because their Savings Throw DC and Spell Proficiency increases. So the higher the level the mage, the more difficult it will be for enemies to make Savings Throws against the mage's Spell Difficulty Check and the easier it will be for the mage to hit with their Cantrips.
Mages have always been weaklings in the beginning levels. This is what a lot of people are missing. Those who don't play D&D tend to expect that their characters are supposed to begin the game as experts in their crafts. They aren't. At Level 1, you are a baby weakling barely better than the average grunt off the streets. Then, as you increase in level, you become more and more powerful in the game. The mage WILL become an OP member of the party as he/she gets to higher levels. In BG1 and 2, I played as a sorcerer. In the beginning, I had to protect him with everything I had all the time. By the end of BG2, my sorcerer was the most powerful member of my team. Nothing could kill him. Time Stop, Chaining 6 spells at one time using Spell Sequencer and such, I could wipe out untold numbers of enemies in just a round or two. It just takes time and lots of levels before you get to that place.
So keep in mind, D&D is about your character growing, and you seeing how different your character is from start to finish. It is about the journey from baby apprentice to master arcanist; from petty thief to skilled assassin or grunt soldier to champion warlord. If they don't limit your mage and such at Level 1 like they do, the whole point of this character growth and development is completely lost.
