No, they’re not inconsistent.
Shareholders of a company can’t vote on behalf of the company in that capacity, and beneficiaries of a trust can’t vote on behalf of a trust in that capacity. This makes sense because a company can have numerous shareholders, and a trust may have many beneficiaries.
In both cases a shareholder or beneficiary can be appointed/authorised to vote on behalf of the company or trust. For a company that would be the person nominated to act on behalf of the company. For a trust, it could be a person authorised to exercise certain powers of the trustee, who is the entity/person who can exercise the right to vote.
Note that for a trust you can have either a corporate trustee or a natural person who is the trustee. In the former case, the authorised representative of the company would be able to vote on behalf of the trust.