(this as any ) is just a Type Assertion that works on dev/compiling time and has no side effects on run time because it is purely a Typescript thing. It can be useful if something related to this like this[whatever] which outputs a TS error because whatever is not defined inside the this TS type. So, this error can be suppressed with (this as any)[whatever]
Also (this as any) is the equivalent to (<any> this)
Note to mention: --suppressImplicitAnyIndexErrors as a compiler option suppresses those kind of possible errors.