In point buy, the racial +2/+1 modifiers become much more pronounced. Without the +1 you can't have a 16 in your main stat and you're always behind races that do. You also have to pay more for the stats without racial bonuses, which translates to having a lower ability score total.
A couple of quick points for clarity:
- The nice thing about the bounded limits of 5e is that you are, quite literally not always behind the character playing a race that is natively well suited to your class; If you both train hard, learn hard, and achieve your optimum, becoming the best individual that you can possibly be, then at the end of the day you will reach the SAME maximum. They have a head start, but the top of the podium is in the same place and you can both reach it. This feeds partially into the other detail;
- You do not pay more for ability scores without racial bonuses and you do not end up with a lower ability score total than a character with different racial modifiers, unless you choose to allocate that way. The costing and point expenditure in point buy happens independently of and prior to the addition of racial ability score bonuses. Remember, with Point buy you can have 15, 15, 15, 8, 8, 8, for a final score total of 72 (after you add your racial 2 and 1), or you can have 12, 12, 12, 13, 13, 13, for a final score total of 78 (after you ass your racial 1 and 2); how you choose to allocate determines your final 'total' numeric score, which I've always felt is a pretty shoddy metric to be using as a comparative Anyway, but it's universal and unaffected by what racial ability bonuses you have or where they go.
- The game is forcefully telling you to do nothing. You can build your character however you please, and know that you will be able to attain the optimums for what you want eventually. If you refuse to build the way you want to because you've decided that it's 'sub-optimal', whatever that means in a roleplaying game, that's entirely a player decision, and one would hope that they only make that decision because doing so makes them happier than building the way they originally wanted to.
Let's take that Eldritch Knight for example - you want strength base as your weapon of choice, and you want to be wise, so as to have good perception. Easy enough, sure:
High Elf adds: Dex +2, Int +1, for a final total score of 74 - in the middle of the range.
You're a fighter, so at level 4 you add 1 to Wisdom and one to Int At 6, you boost wisdom again, and at 8 you do it again. At 12 you start on Strength, and at 14 and 16 you can do the same At 19, you've got your Strength and Wisdom capped out at 20, so you can raise your Con further, maybe boost your spell DC with Int, or perhaps take a feat. You could do this earlier - boosting whichever score you felt needed it the most at the time, of course.
Point is - if you WANT to make an EK with super high wisdom, you certainly can. EK uses at least one martial ability score for their weapon use, is a fighter and so is likely considered a front liner, and uses Int as their casting ability, so if you WANT to spread yourself over Wisdom as well as the abilities core to the class, you certainly can - that's your choice. You'll end up lacking in some area, most likely, because you can't be excellent at every ability score, and making 4 scores competitively high is a big ask for anyone. Maybe you don't necessarily intend to have the wisdom of literal demigods, and just want to be pretty perceptive - you can allocate those points elsewhere or substitute on of them for a perception-based feat. all perfectly valid choices.
Will you have an easier time of it if you play into the natural-born propensities of your birth race? Probably. Is it necessary? No. Is the game 'forcefully compelling' you do do so? Not in a month of Sundays - that's all player-imposed.
If a player literally cannot have fun playing their character unless they are optimally streamlined, that's the player's own problem - that's not the game, and it's not the game's fault or duty to accommodate their narrow purview of fun either; that player is perfectly capable of using the system TO create an optimally streamlined character if that's what they want and enjoy. If they'd rather build a character to suit the roleplay concept they think they'll enjoy instead they can do that too. It's a roleplaying game - play the character you want to play and have fun with it.
