If I click on someone's profile and scroll through their questions/answers posted and upvote a lot of them, can this be removed as looking suspicious or spammy? I know this happens with downvotes, but does it apply to upvotes as well?
Yes. Applies to upvotes. (disclosure - I am a Mod at Money.SE) Some time ago, soon after I got my diamond, I saw activity from a member offering edits. These came in as items that needed to be voted on, or approved by a mod. The member was within 100pts of rep to have the privilege to edit with no need for approval. I searched on his profile and "serial-upvoted" 10 answers of his. The next day, I saw he still needed his edits approved as my upvotes were detected and cancelled. The system cannot detect motivation, so my 'good intentions' didn't negate the fact that I tripped an internal process intended to detect fraudulent voting.