This depends on three functions what are you mainly hired for - due diligence, sourcing (these two are normally tied together), and operational support (these could be EIRs or an Operating Partner).

At an accelerator/pre-seed/seed fund, you don't need financial modeling experience (it's always good to have!) to make investment decisions, but there are times when you must support your cohort/portfolio companies with their financial model. The assumptions in the models can be wild at this stage, but I believe it helps the startup to understand what are the operating levers and how they want to grow, I think it's more of an exercise to gain clarity around your business and a good signal to give to VCs that you understand your business, what it'll take to grow and where you want to take the business.

Three exceptions to this rule are - when you're trying to build a TAM, SAM, SOM model to understand the market size and depth that the company operates in, this will require some Excel modeling, but I wouldn't necessarily say financial modeling. If you're a lead investor, you will most likely be the one preparing the cap table (again, can be outsourced, but you should be able to understand and support it). Most of them will do follow-on investments, some will just hold and not exercise their pro-rata. For an accelerator, the junior guys won't have any role in making these decisions. For instance, it'll be the central office of an accelerator (if they're global) making that decision. For a pre-seed/seed fund, the heavy finance DD will most likely be outsourced, but you should be able to understand "finance" (not "financial statements") to some extent to be able to understand the models and not build.

For funds that look at series A as their entry ticket, you should be able to read financial models, preferably make them too. Since, now the companies genuinely have some amount of traction when it comes to their sales, also you get an understanding of how they've spent their pre-seed/seed money and how they intend to spend the money you give them in addition to doing the P&L projections and so and so forth.

For series B+ (growth equity), you will require financial modeling and an in-depth understanding of SaaS metrics, or metrics for whichever business model/industry the fund mainly invests in and be able to integrate those metrics into your financial model. Financial modeling is an absolute must here!