As a tech lead, you had better be able to express yourself. Not the woolgathering flights of fancy, where “We could do ___”. But concrete examples. Hard drawings. Prototypes.
People will wander and wonder around a concept and an idea until you give them something to point to. Words are not enough.
You have to be daring enough to draw the worst straw man, the ugliest example to free the team up to make progress. And you have to accept that if your team is good, they’re going to shred it.
In fact you should start your first drafts in the hope that there’s a really clever person on your team who will shred it. Yours are not the important ideas. Your role is to break the inertia.
Get the team started and polarised. Give them something to join or resist, but don’t allow them to just sit.
Hesitate and all will be lost.