Possible but Maybe not profitable like before. there are so many restrictions. Transactions fees are huge nowadays, but if you have a lot of money to cover transactions fee then maybe you can make profit from market. And as market is so volatile, so it is possible that your token takes alots of time to deposited in other exchange and price get down. Then you make lose. Manual process isn't worth now everything is technologcal advance and bot trading is ahead of taking advantage in this field
Manual process is still there and it's still being preferred by some users. I won't talk negative about it because if without it, we won't get where we are now. On the other hand, I think I already heard of arbitrage bots for use in trading. So, automizing it might be possible now. But as you said, it may only cost us more because for sure, bots like this are not free. The fees for some cryptos are also costly now and then they can now move slower, so going arbitrage on them might be less effective now. We can still try on other cryptos (preferably the new ones) since they are not that crowded yet. We must only be careful for a possible rug pull.