Because super_sliver_list >=0.2.0-dev.1 depends on collection ^1.18.0 and every version of flutter from sdk depends on collection 1.17.2, super_sliver_list >=0.2.0-dev.1 is incompatible with flutter from sdk.
So, because xxx depends on both flutter from sdk and super_sliver_list ^0.2.0, version solving failed.
Because super_sliver_list >=0.2.0-dev.1 depends on collection ^1.18.0 and every version of flutter from sdk depends on collection 1.17.2, super_sliver_list >=0.2.0-dev.1 is incompatible with flutter from sdk. So, because xxx depends on both flutter from sdk and super_sliver_list ^0.2.0, version solving failed.