It's using the same engine as the Space Shuttle (literally - it's using refurbished engines from the Space Shuttle [1]), exact same solid rock boosters with all their flaws, and so on. One difference from the Shuttle is that the SLS doesn't even have a pretext of reuse. It's a single-use only rocket.

One other big difference is that it's also obsolete before it's even complete. It can lift about 50% more than a Falcon Heavy for what will be orders of magnitude greater cost, to say nothing of comparisons to Starship. So there's no viable use case for it to ever actually be used, except for corruption. So it will be used, but it's just been a monumental waste of money that could have instead been directed towards meaningful progress in space. The entire Apollo program which spanned 11 years and started from zero, only cost $180 billion in total, inflation adjusted - less than $18 billion a year. NASA's current budget is $26 billion per year.

[1] - https://en.wikipedia.org/wiki/Space_Launch_System#Core_stage