I'm having trouble seeing how Euro play preceding NBA has all that much to do with selection to the HOF . If it's a borderline selection or a unique case such as Arvydas Sabonis, but other than that I don't see it.
On the other hand, I'll defer to anyone who knows more than I do (which is everyone) about the impact any particular Euro/Int has had on basketball from an outside of the USA perspective. That argument I can't counter.
But as far as 4 or 5 years of Euro stats and honors -- I can't see that as too much different than a college phenom (back in the 4-year days) going on to have an above average NBA career. Let's imagine if Larry Bird after his terrific college play at Indiana State (3 years, 30ppg, 13 rpg, 4.6 apg...) went on to have an above average NBA career for 10 years or so (remember, Bird was 23 his rookie year). Would anyone think he should be in the HOF? In fact, most people would have probably considered him a bust.
I don't think Euro play preceding the NBA has much impact now in the same way that NCAA play does not have much impact. It is only for the first few guys who made the transition.
Think of it from another angle. If nobody from the NCAA had ever made it to the NBA before then it would be pretty remarkable to see the first couple of guys do it. That is how I see some of those early 90s guys (Marciulionis, Vlade, Petrovic).
The question to me is Kukoc also included in that group or he is considered outside that group. I always viewed him as not the same but closely linked to them. So where does that leave Kukoc?
Kukoc was the first Euro I remember being excited about coming over to the NBA. Wondering how good he could be. He was the first guy we really heard about before he came over. Sabonis yeah in the 80s but he didn't come over until 1995 when he was old and battered. Kukoc was the premier star of European basketball and he was the first to come with expectations.
Petrovic was the first star player but that was after a few years of toiling on the end of Portland's bench. Vlade was considered a solid but underachieving soft NBA center (useful but unexceptional) until the mid-90s when he got some more credit for his abilities. Marciulionis was better than Vlade but Sarunas got hurt just as he was breaking out.
This was the state of the Euros when Kukoc arrived in 1993. One starter, two starter quality players. It was the early days. I mean, Petrovic made his first All-NBA team the year before Kukoc arrived. Petrovic was wrongly overlooked for the All-Star game so none of them had made an ASG (neither did Kukoc).
This was still very early on in terms of Euros being (1) accepted as legit NBA level players (2) Valued as key components of teams (3) thirdly sought after in drafts, trades and free agency. It was all a process. Kukoc to me played a big role in that process (even though he was not among the first 3).