Potentially yes, but not necessarily. Theres more ways to get tech than simply trading after all. Or trading fairly. Certainly at a 1:1 trade ratio we may have equivalent tech. And what happens down the road when perhaps a level 3 or 4 tech is traded? 1 lower than the trader's tech will still be a huge boost.
But then we're in the realm of having to trade tech to remain competitive. Theres no reason not to trade tech right now, and every reason for it. There should be some downside.
So. Level 1 then? Since if bought at 0, and we can use that for innovations, and if 0 + 1 innovation = level 1 tech, the sidebar barely exists. Seems like added bookkeeping for no real purpose. Since the moment you use it in an innovation succesfully its native.
Anywho I meant to do this.
1) People will bitch, you can't outright forbid tech trading without a good reason.
2) Dependency on a dice roll will just lead to people spamming trade actions until they stick.
3) Is potentially viable, they are gaining tech. As it stands it is without cost. On the plus side, implementing either 3 or 4, will lead to people developing their tech along their own paths, leading to a more unique layout of civs.
To me this is the most viable option.
4) Is also viable. Since we all have contact with each other, and clearly speak the same language. Emigration would likely occur among people with knowledge.
5) Potentially some kind of technological breakthrough we must reach before we can even start trading knowledge? A whole 'Writing' type tech. Though that may not fit with the current tech system.