The short answer
Yes for three groups: new younger players, returning veterans with nostalgia to spend, and parents choosing a first MMO. The game is actively updated, the community is alive, and the free opening world remains one of the most generous on-ramps in the genre.
What changed since you left
If you last played years ago: multiple new worlds extend the storyline well past whatever you remember as the end, quality-of-life updates cleaned up the early game, and seasonal events now run almost continuously. Your old account almost certainly still works, and logging into a max-level wizard from 2012 is a rite of passage.
The real cost of playing seriously
Free gets you Wizard City. After that, budget for membership or permanent zone purchases with Crowns. Casual returners should price a single membership month against how much story they want, and zone-buying makes sense mainly if you replay content on multiple wizards.
When the answer is no
If you need modern graphics, fast-paced action combat, or a fully free endgame, this is not your game and no amount of nostalgia fixes that. Old School RuneScape gives free players dramatically more, and Neverwinter gives action combat. Know which itch you are scratching.
Put it to work
Wizard101 is free to play. Load in and try this guide with your own character.
Play Wizard101 free