It seems to me like we're always story wise meant to have party members with us but they don't always remember to, or feel the need, to shove in some reference. For example the Susano trial description says nobody can defeat a primal on their own. Lyse in 4.1 says 'it takes more than three to beat a primal' and her and Raubahn are in portant in helping us take down Lakshmi before Fordola's barrier gives out.

With Ifrit, there's an npc you can talk to you says 'hey you can slip out here if you need to' or something like that leaving room for the WOL to have potentially gone out and gotten aid as well.

But the game can be inconsistent with power scaling. Like what do we do between our second curbstomp from Zenos and Ala Mhigo that allows us to actually fight him? Why was Shinryu such a big deal Popolymo had to sacrifice himself to buy time and we risked unleashing Omega to deal with it...then in the end Zenos possesses it and we just kill it like it was any other monster?

Sometimes we get some lore to help explain things. The first fight with Nidhogg we had Estinien using one of the dragon's eyes against him. In the second fight, we get a buff from Hrasvalgr's eye. Sometimes we just kick ass like against Thordan and Shinryu.