Correct! Inlining obviously costs CPU, code cache space, and makes the receiver method bigger so that it's less likely it will be inlined itself. If there ever is a decompilation occuring, the inlining efforts were pretty much wasted.
However it must be pointed out that inlining enables further optimisations.
The tradeoffs are more complicated for a jit, but for an aot compiler it’s one of the most important optimisations in the pipeline.