This is a GREAT question! There are SO MANY options out there for learning music these days - it's actually a wonderful time to learn music because of how many pathways there are!
First, I will say it truly depends on student goals and learning styles as to what may be the most beneficial. Lessons aren't for everyone, and neither are tutorial videos - there's no one-size-fits-all approach when it comes to learning music.
If a potential student has a goal to learn a very specific song for a very specific event, a tutorial video might be exactly what they need: it gets them to their goal quickly, and doesn't spend any time on anything else. They can pause and rewind as necessary to review sections along the way. Potential downsides include not learning to read sheet music, not fully understanding what they're playing if the tutorial is simply showing them where to place their hands, and being able to play a specific song at a level beyond their actual reading/playing ability - which can lead to frustration if they decide they'd like to learn more.
If a potential student is looking to start a lifelong journey playing music, lessons may be a better option. In lessons, each class is tailored to the student's knowledge and abilities on that day, introducing concepts when students are ready to absorb them. They'll be exposed to LOTS of general music info: reading sheet music, playing with expression and dynamics, how to recognize intervals, ear training, sight reading, and much more.
With that in mind, though, some students may find lessons move “too slowly” to get them to their goal of playing a specific song. In my studio, I encourage students to look up tutorials and how-to videos for songs they'd like to learn on their own, in conjunction with what we learn in class. This has been a good blend so far of ensuring students understand concepts and technique while also being able to play songs of their choosing that may be a bit beyond their current reading or playing level if we were to learn strictly via sheet music.
Long story short, there's no “right way” to learn music. I encourage all potential students to choose the option - or the hybrid option - that works best for their goals!