why Newtonsoft.Json too big when build native aot

[NCLnclNCL]

if i build with System.Text.Json it is 6 mb but it i build with Newtonsoft.Json it is 16 mb, both have the same same size of dll files

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Issue Details

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if i build with System.Text.Json it is 6 mb but it i build with Newtonsoft.Json it is 16 mb, both have the same size of dll files

Author:	NCLnclNCL
Assignees:	-
Labels:	area-System.Text.Json
Milestone:	-

[hez2010]

Newtonsoft.Json doesn't have NativeAOT support at all, so it instead rooting the whole assembly regardless of whether a type will be used or not.
While System.Text.Json has the support if you are using source generator, so only the necessary part of code will be kept in the binary.