No. In Jan 2018 there was nothing, in 2019 there is NSMBU and even if you don't want to accept this idea : this game will keep selling just constantly, it will keep selling at a regular pace in 2 years still while everybody will have forgotten RDR2...EVERY 5-6 years old children are just a bit too young to handle Mario Odysee but NSMBU is perfect for them.
Would Super Mario Maker 2 kill its legs?
No. Again, for a 5-6 years old child, it is too complex. My nephew wanted Splatoon and Mario Odysee, I can barely let him play alone more than a minute on Odysee, and on Splatoon it is almost impossible. SMM2 is not adapted for 5-6.