As with all revivals, they always have to work extra hard to live up to the original. That's the simple truth. Nostalgia may play a factor, but the reality is that the original series featured many fully original sketches. Most of those sketches either launched successful spin-off shows or carriers for the actors.
In contrast, the 2019 revival lacks that original sketch content. Instead, they rely on trends and parodies of already existing shows and impersonations of real life people. Parodies are not bad things on their own. Well done parodies are hilarious. However, original writing is a must if this revival wants to survive past its first season. If this revival intends to rely only on parodies, it will struggle to last for a long run. This will be the case because these sketches are going to be time sensitive and fail to draw an audience after a very short period of time. The original relied on creating its own characters and situations that lends itself to a timeless feel. This new series is sadly only relying on trends. Since trends only last for a very short period of time, this is a situation of short term gain, long term loss. The new series won't be memorable and last long if the choice of sketch content doesn't change.
As for the new actors, I imagine that this is probably most of these kids first major shows to be working on. It's clear that they weren't very comfortable in their roles and positions. Hopefully, they will get more comfortable with time, but the initial acting was stiff and lacked believability and fluidity, both in opening sequence and in the actual sketches.
