You have literally said it so yourself - it's only been a week since the season ended and with Euro 2020 taking place this summer, it's not going to be straightforward or fast to complete a transfer especially if that player is playing at the tournament. Some of the agitation that has been going on around here seems to be down to people's transfer fantasy not happening more than anything else.
I don't disagree that we need some additions but again, compared to past summers or those years you mentioned, the current squad is much better than those back then. We have already got good players coming through the academy and we already spent big last summer. 2-3 new additions needed yes but at the same time, it's also about improving the current group of players that we have, something that Tuchel has already spoken about and is relishing to do.
Getting a new striker may or may not happen for obvious reasons. Spurs won't sell Kane to us. Haaland isn't going anywhere. Lukaku already said he wants to stay at Inter and Inter don't want to sell him, although that could depend if they are able to sell 1-2 others but even then, not everyone seems to think he's good, including you. Other than those 3, there's no one obvious and we would then have to take a risk with someone low key. Either that or we somehow stick with what we have, including Giroud.