Deep pockets are not a get out of jail free card. If a case escalates to the SCOTUS there will be many firms that submit amicus curiae outlining their position on the matter and how it threatens their rights. Those people, arguably, represent more money and influence than Google, OpenAI, Microsoft, etc. So if we accept the premise that all legal matters are decided on a basis of pure politics as mediated by money, then ultimately every court battle is a battle to assert that your actions don't actually affect the interests of interested parties and that you'll fight them if they try to assert otherwise, and on that count it is reasonable to surmise that there are more interested parties with deeper pockets than any firm or firms fielding LLMs that might be caught up in a lawsuit over this.
Ultimately, if an author can demonstrate protectable expression has been incorporated into an AI's training set and is emitted by said AI, no matter how small, they've got a case of copyright infringement. That being the case, LLM-based companies are going to suffer death by a thousand paper cuts.
We just got through talking about how the players involved have deep pockets, and have a vested interest in seeing their way prevail... so cheap doesn't matter, likely is malleable, which leaves only "fast" which I do not contest.
Ultimately, if an author can demonstrate protectable expression has been incorporated into an AI's training set and is emitted by said AI, no matter how small, they've got a case of copyright infringement. That being the case, LLM-based companies are going to suffer death by a thousand paper cuts.