In the same dictionary (研究社), I found two examples that seem to say the thing.
However, one uses する while the other, させられる。

> あの子の勉強ぶりには感心する  
>  I'm very impressed by how this kid studies.

> いつもながら, 彼女の仕事ぶりには感心させられる  
>  As usual, the way she works is impressive.

How can both active and causative form be plugged into the same grammatical
slot, without a change in meaning?
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2022-04-12T05:36:19.920
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question
grammar
Why are both 感心する and 感心させられる useable in Xに感心+V?
に in the first sentence can be understood as indicating the target of the
subject’s emotion, or what it is directed towards.

> あの子の勉強ぶりには感心する。

When the subject is the person as in this example, English expresses a
relationship like this using the passive voice. Japanese uses the active
voice. If you ignore this difference in voice, に roughly corresponds to a
preposition such as “by” and “with.” With verbs for some other emotions, “at”
is also used, and this might bring up a closer image to に than “by” or “with.”

I don’t know what grammatical explanation is given to this, but に in the
second sentence could be seen as having a dual function. Let’s use the
following modified version of the first sentence as an example.

> あの子の勉強ぶりには感心させられる。

The first, probably primary, role is as the marker of the agent of the action
described by the verb in the passive, which in this case is the causative
感心させる. This sentence is very similar in construction to the English
translation for the first, with the transitive verb 感心させる being the direct
translation of the verb “to impress,” which is used in the passive, and に
playing a similar role to “by.”

> I'm very impressed **by** how this kid studies.

On the other hand, this に could also be seen as playing the same role as に in
the first sentence. When something impresses you, the emotion that results is
directed towards that thing. The two are one and the same.

Either way, yes, に can be used in both. The first sentence with する sounds more
direct and assertive to me with focus on how the speaker feels. The second
with させられる sounds to me as if the speaker is trying to sound objective
shifting focus to what impresses them, rather than how they feel.
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answer