Employer HDHP vs. PPO w/same deductible, OOP max

I chose a traditional PPO for 2023 because the upfront costs are way lower. But looking at the HDHP my company offers vs. the PPO, the deductible and OOP max are exactly the same for both, as well as the coinsurance.

HDHPPPOPremium20/month70/monthDeductible (Medical/Rx combined)35003500OOP Max50005000Coinsurance20%20%Employer HSA contribution600/yearN/APCP, Specialists20% after deductibleHave copays, don’t count towards deductiblePrescriptionsCopays after deductibleSame copays don’t count towards deductibleSurgery20% after deductible20% after deductible

I looked at my claims so far for the year, and because I’m on a very expensive brand-only med and have a lot of specialist visits, I’d have hit the deductible in mid-January and the OOP max in February if I were on the HDHP plan and paid the full cost of everything. So far, since none of my visits or prescriptions have counted towards my deductible, I still have my entire $3500 deductible to fill and the copays put me at about 1/4 of the way into my OOP max.

I understand that this involves paying $5k at the beginning of the year, but if I’m planning to have surgery in mid to late 2024 the HDHP seems like a better deal since I won’t have to pay $3500 deductible + part of the OOP max on top of the 20% of the surgery cost, just the 20% of the surgery cost.

The 20% of a specialist visit (after deductible) is the same or better deal than the PPO copay.

I’m thinking about choosing the HDHP for next year, but it seems like there’s some sort of catch I’m not getting beyond the having to pay up front for everything at the beginning of the year.