Here is a data point.
1) I bought Assasin Creed's Vahalla - Limited edition at $73 from Shopee. The lowest price that I can get. During days of plays sale that ended just a couple days ago. The gold edition is just $79 and contains more DLC, etc. The standard edition was below $60
2) I bought Spiderman Miles Morales at $63 from Shopee. I learnt a lesson that this US version will play just fine but can't redeem the pre-order DLC with Singapore PSN. I can't also upgrade to top-up and get ultimate version (the remastered spiderman). During the days of play sale, the ultimate version is much cheaper.
The only good deals that I can get is those pre-owned PS4 disc games, may be in the future pre-owned PS5 games. For now, seems the physical disc prices (even with discounted in Sony store or shopee), can't beat digital price.
I bought Yakuza Legendary Hero Pack and Ghost of Tsushima around $50 each. Seems bundled game with all DLC would be cheaper in digital than buying base + DLCs.
For point no. 2) You can always create a US region psn to redeem the dlc & get the remastered spiderman deal.. Anyway for new games, the physical copy will be cheaper (via shopee & voucher/cc promo etc) and not to mention normally can re-sell it to recover at least 70% of the cost.
As for older games, yes I agree digital one which are on sales definitely will be a better deal.