Would this requirement to start from ground zero in current LLMs be an artefact of the requirement to have a "multi-tenant" infrastructure? Of course OpenAI an

Would this requirement to start from ground zero in current LLMs be an artefact of the requirement to have a "multi-tenant" infrastructure? Of course OpenAI and Anthropic want to be able to reuse the same servers/memory for multiple users, otherwise it would be too expensive. Could we have "personal" single-tenant setups? Where the LLM incorporates every previous conversation?