Now that we're about a month into Silksong, I will say the initial difficulty was much higher than I expected as a pretty seasoned Hollow Knight player, but the game actually seems to get easier as you go along and get more powerful and get more power ups. When you're into Act 2 the challenges are much more on the boss side than mid/late Act 1 where you're basically trying to not die the entire time.
I think they could have balanced the early game a little better honestly, offering some power ups for sale (that way you can grind for currency and then buy the upgrades), nerfing some early game boss damage, etc. Difficulty is still part of the game though, where you need to die to find all the ways NOT to do something. But there could be a better balance between casual exploration (including routine enemy battles) vs difficult bosses. I found there was too much of the game limited early on by very difficult fights.
As for the game itself, I think the level design, artwork, music, etc are all on par with the first game which is some of the best of all time. Lots of interesting regions to explore with a lot of character and charm. The world is definitely much bigger but I found it to feel a bit linear for the first act. I think that's again where the exploration would be more intriguing.
The mechanics of the game are really different than Hollow Knight as well. In HK you had charms which were the way you could power up and change the strategy of the game. In Silksong you have crests that really impact the mechanics and feel, but are much more pros/cons than charms which were straight power ups. But you have tools now which are kind of power ups that need to be replenished. It feels overall a little more clunky to use the tools rather than integrating charms to gameplay.
I definitely feel a lot better about the game than I did at the end of the first week. I'm not sure if it tops HK overall because my first playthrough on that game was more fun and less stressful. But you definitely get a ton of game for $20.